Added the ability to dynamically remove or add EQ unit to save battery when EQ unit is not needed

Fixed crash in the STKHTTPDataSource.

ExampleApp/ExampleApp.xcodeproj/project.pbxproj

@@ -418,6 +418,7 @@
 				ARCHS = "$(ARCHS_STANDARD_INCLUDING_64_BIT)";
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_LAUNCHIMAGE_NAME = LaunchImage;
+				GCC_OPTIMIZATION_LEVEL = 0;
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
 				GCC_PREFIX_HEADER = "ExampleApp/ExampleApp-Prefix.pch";
 				INFOPLIST_FILE = "ExampleApp/ExampleApp-Info.plist";

ExampleApp/ExampleApp/AppDelegate.m

@@ -21,24 +21,27 @@
 
 @implementation AppDelegate
 
-
 -(BOOL) application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions
 {
     NSError* error;
     
     [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:&error];
-
+	[[AVAudioSession sharedInstance] setActive:YES error:&error];
+    
+    Float32 bufferLength = 0.1;
+    AudioSessionSetProperty(kAudioSessionProperty_PreferredHardwareIOBufferDuration, sizeof(bufferLength), &bufferLength);
+    
     self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
     
 	self.window.backgroundColor = [UIColor whiteColor];
     
-	audioPlayer = [[STKAudioPlayer alloc] initWithOptions:STKAudioPlayerOptionFlushQueueOnSeek];
+	audioPlayer = [[STKAudioPlayer alloc] initWithOptions:(STKAudioPlayerOptions){ .flushQueueOnSeek = YES, .enableVolumeMixer = NO, .equalizerBandFrequencies = {50, 100, 200, 400, 800, 1600, 2600, 16000} }];
 	audioPlayer.meteringEnabled = YES;
+	audioPlayer.volume = 1;
 	
-	AudioPlayerView* audioPlayerView = [[AudioPlayerView alloc] initWithFrame:self.window.bounds];
+	AudioPlayerView* audioPlayerView = [[AudioPlayerView alloc] initWithFrame:self.window.bounds andAudioPlayer:audioPlayer];
     
 	audioPlayerView.delegate = self;
-	audioPlayerView.audioPlayer = audioPlayer;
     
     [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
     [self becomeFirstResponder];

ExampleApp/ExampleApp/AudioPlayerView.h

@@ -51,6 +51,7 @@
     UILabel* label;
     UILabel* statusLabel;
 	UISlider* slider;
+    UISwitch* enableEqSwitch;
     UISwitch* repeatSwitch;
 	UIButton* muteButton;
 	UIButton* playButton;
@@ -65,4 +66,6 @@
 @property (readwrite, retain) STKAudioPlayer* audioPlayer;
 @property (readwrite, unsafe_unretained) id<AudioPlayerViewDelegate> delegate;
 
+- (id)initWithFrame:(CGRect)frame andAudioPlayer:(STKAudioPlayer*)audioPlayer;
+
 @end

ExampleApp/ExampleApp/AudioPlayerView.m

@@ -47,12 +47,14 @@
 @implementation AudioPlayerView
 @synthesize audioPlayer, delegate;
 
-- (id)initWithFrame:(CGRect)frame
+- (id)initWithFrame:(CGRect)frame andAudioPlayer:(STKAudioPlayer*)audioPlayerIn
 {
     self = [super initWithFrame:frame];
 	
     if (self)
 	{
+        self.audioPlayer = audioPlayerIn;
+        
 		CGSize size = CGSizeMake(220, 50);
 		
 		playFromHTTPButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
@@ -97,7 +99,12 @@
         
         size = CGSizeMake(80, 50);
         
-        repeatSwitch = [[UISwitch alloc] initWithFrame:CGRectMake((320 - size.width) / 2, frame.size.height * 0.15 + 180, size.width, size.height)];
+        repeatSwitch = [[UISwitch alloc] initWithFrame:CGRectMake(30, frame.size.height * 0.15 + 180, size.width, size.height)];
+        
+        enableEqSwitch = [[UISwitch alloc] initWithFrame:CGRectMake(320 - size.width - 30, frame.size.height * 0.15 + 180, size.width, size.height)];
+        enableEqSwitch.on = audioPlayer.equalizerEnabled;
+        
+        [enableEqSwitch addTarget:self action:@selector(onEnableEqSwitch) forControlEvents:UIControlEventAllTouchEvents];
 
         label = [[UILabel alloc] initWithFrame:CGRectMake(0, slider.frame.origin.y + slider.frame.size.height + 10, frame.size.width, 25)];
 		
@@ -107,11 +114,10 @@
 		
         statusLabel.textAlignment = NSTextAlignmentCenter;
 		
-		
 		meter = [[UIView alloc] initWithFrame:CGRectMake(0, 450, 0, 20)];
 		
 		meter.backgroundColor = [UIColor greenColor];
-        
+		
 		[self addSubview:slider];
 		[self addSubview:playButton];
 		[self addSubview:playFromHTTPButton];
@@ -124,6 +130,7 @@
         [self addSubview:stopButton];
 		[self addSubview:meter];
 		[self addSubview:muteButton];
+        [self addSubview:enableEqSwitch];
         
 		[self setupTimer];
 		[self updateControls];
@@ -132,6 +139,11 @@
     return self;
 }
 
+-(void) onEnableEqSwitch
+{
+    audioPlayer.equalizerEnabled = self->enableEqSwitch.on;
+}
+
 -(void) sliderChanged
 {
 	if (!audioPlayer)

ExampleAppMac/ExampleAppMac.xcodeproj/project.pbxproj

@@ -432,7 +432,7 @@
 					"$(SRCROOT)/../StreamingKit/StreamingKit",
 				);
 				INFOPLIST_FILE = "ExampleAppMac/ExampleAppMac-Info.plist";
-				MACOSX_DEPLOYMENT_TARGET = 10.8;
+				MACOSX_DEPLOYMENT_TARGET = "";
 				OTHER_LDFLAGS = "-ObjC";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				WRAPPER_EXTENSION = app;
@@ -452,7 +452,7 @@
 					"$(SRCROOT)/../StreamingKit/StreamingKit",
 				);
 				INFOPLIST_FILE = "ExampleAppMac/ExampleAppMac-Info.plist";
-				MACOSX_DEPLOYMENT_TARGET = 10.8;
+				MACOSX_DEPLOYMENT_TARGET = "";
 				OTHER_LDFLAGS = "-ObjC";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				WRAPPER_EXTENSION = app;

ExampleAppMac/ExampleAppMac/AppDelegate.m

@@ -40,13 +40,22 @@
 	[[self.window contentView] addSubview:playFromHTTPButton];
 	[[self.window contentView] addSubview:meter];
 	
-	audioPlayer = [[STKAudioPlayer alloc] init];
+	audioPlayer = [[STKAudioPlayer alloc] initWithOptions:(STKAudioPlayerOptions){ .enableVolumeMixer = NO, .equalizerBandFrequencies = {50, 100, 200, 400, 800, 1600, 2600, 16000} } ];
 	audioPlayer.delegate = self;
 	audioPlayer.meteringEnabled = YES;
-	
+	audioPlayer.volume = 0.1;
+    
+    [self performSelector:@selector(test) withObject:nil afterDelay:4];
+    [self performSelector:@selector(test) withObject:nil afterDelay:8];
+    
 	[NSTimer scheduledTimerWithTimeInterval:0.01 target:self selector:@selector(tick:) userInfo:nil repeats:YES];
 }
 
+-(void) test
+{
+    audioPlayer.equalizerEnabled = !audioPlayer.equalizerEnabled;
+}
+
 -(void) playFromHTTP
 {
 	[audioPlayer play:@"http://fs.bloom.fm/oss/audiosamples/sample.mp3"];

README.md

@@ -16,7 +16,7 @@ The primary motivation of this project was to decouple the input data sources fr
 * Optimised for low CPU/battery usage (0% - 1% CPU usage when streaming).
 * Optimised for linear data sources. Random access sources are required only for seeking.
 * StreamingKit 0.2.0 uses the AudioUnit API rather than the slower AudioQueues API which allows real-time interception of the raw PCM data for features such as level metering, EQ, etc.
-* Example apps iOS and Mac OSX provided.
+* Example apps for iOS and Mac OSX provided.
 
 ## Installation
 

StreamingKit/StreamingKit.xcodeproj/project.pbxproj

@@ -565,7 +565,7 @@
 					"DEBUG=1",
 					"$(inherited)",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 10.8;
+				MACOSX_DEPLOYMENT_TARGET = "";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
 			};
@@ -582,7 +582,7 @@
 				GCC_ENABLE_OBJC_EXCEPTIONS = YES;
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
 				GCC_PREFIX_HEADER = "StreamingKitMac/StreamingKitMac-Prefix.pch";
-				MACOSX_DEPLOYMENT_TARGET = 10.8;
+				MACOSX_DEPLOYMENT_TARGET = "";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
 			};

StreamingKit/StreamingKit/STKAudioPlayer.h

@@ -78,10 +78,22 @@ typedef enum
 }
 STKAudioPlayerErrorCode;
 
-typedef enum
+typedef struct
 {
-	STKAudioPlayerOptionNone = 0,
-	STKAudioPlayerOptionFlushQueueOnSeek = 1
+    /// If YES then seeking a track will cause all pending items to be flushed from the queue
+    BOOL flushQueueOnSeek;
+    /// If YES then volume control will be enabled on iOS
+    BOOL enableVolumeMixer;
+    /// A pointer to a 0 terminated array of band frequencies (iOS 5.0 and later, OSX 10.9 and later)
+    Float32 equalizerBandFrequencies[24];
+	/// The size of the internal I/O read buffer. This data in this buffer is transient and does not need to be larger.
+    UInt32 readBufferSize;
+    /// The size of the decompressed buffer (Default is 10 seconds which uses about 1.7MB of RAM)
+    UInt32 bufferSizeInSeconds;
+    /// Number of seconds of decompressed audio is required before playback first starts for each item (Default is 0.5 seconds. Must be larger than bufferSizeInSeconds)
+    Float32 secondsRequiredToStartPlaying;
+    /// Number of seconds of decompressed audio required before playback resumes after a buffer underrun (Default is 5 seconds. Must be larger than bufferSizeinSeconds)
+    Float32 secondsRequiredToStartPlayingAfterBufferUnderun;
 }
 STKAudioPlayerOptions;
 
@@ -117,6 +129,9 @@ typedef void(^STKFrameFilter)(UInt32 channelsPerFrame, UInt32 bytesPerFrame, UIn
 
 @interface STKAudioPlayer : NSObject<STKDataSourceDelegate>
 
+/// Gets or sets the volume (ranges 0 - 1.0).
+/// On iOS the STKAudioPlayerOptionEnableMultichannelMixer option must be enabled for volume to work.
+@property (readwrite) Float32 volume;
 /// Gets or sets the player muted state
 @property (readwrite) BOOL muted;
 /// Gets the current item duration in seconds
@@ -125,6 +140,8 @@ typedef void(^STKFrameFilter)(UInt32 channelsPerFrame, UInt32 bytesPerFrame, UIn
 @property (readonly) double progress;
 /// Enables or disables peak and average decibel meteting
 @property (readwrite) BOOL meteringEnabled;
+/// Enables or disables the EQ
+@property (readwrite) BOOL equalizerEnabled;
 /// Returns an array of STKFrameFilterEntry objects representing the filters currently in use
 @property (readonly) NSArray* frameFilters;
 /// Returns the items pending to be played (includes buffering and upcoming items but does not include the current item)
@@ -239,4 +256,7 @@ typedef void(^STKFrameFilter)(UInt32 channelsPerFrame, UInt32 bytesPerFrame, UIn
 /// Return values are between -60 (low) and 0 (high).
 -(float) averagePowerInDecibelsForChannel:(NSUInteger)channelNumber;
 
+/// Sets the gain value (from -96 low to +24 high) for an equalizer band (0 based index)
+-(void) setGain:(float)gain forEqualizerBand:(int)bandIndex;
+
 @end

StreamingKit/StreamingKit/STKAudioPlayer.m

@@ -52,13 +52,51 @@
 #define STK_LOWPASSFILTERTIMESLICE (0.0005)
 
 #define STK_DEFAULT_PCM_BUFFER_SIZE_IN_SECONDS (10)
-#define STK_DEFAULT_SECONDS_REQUIRED_TO_START_PLAYING (0.1)
+#define STK_DEFAULT_SECONDS_REQUIRED_TO_START_PLAYING (1)
+#define STK_DEFAULT_SECONDS_REQUIRED_TO_START_PLAYING_AFTER_BUFFER_UNDERRUN (7.5)
 #define STK_MAX_COMPRESSED_PACKETS_FOR_BITRATE_CALCULATION (2048)
 #define STK_DEFAULT_READ_BUFFER_SIZE (64 * 1024)
 #define STK_DEFAULT_PACKET_BUFFER_SIZE (2048)
 
 #define LOGINFO(x) [self logInfo:[NSString stringWithFormat:@"%s %@", sel_getName(_cmd), x]];
 
+static void PopulateOptionsWithDefault(STKAudioPlayerOptions* options)
+{
+    if (options->bufferSizeInSeconds == 0)
+    {
+        options->bufferSizeInSeconds = STK_DEFAULT_PCM_BUFFER_SIZE_IN_SECONDS;
+    }
+    
+    if (options->readBufferSize == 0)
+    {
+        options->readBufferSize = STK_DEFAULT_READ_BUFFER_SIZE;
+    }
+    
+    if (options->secondsRequiredToStartPlaying == 0)
+    {
+        options->secondsRequiredToStartPlaying = MIN(STK_DEFAULT_SECONDS_REQUIRED_TO_START_PLAYING, options->bufferSizeInSeconds);
+    }
+    
+    if (options->secondsRequiredToStartPlayingAfterBufferUnderun == 0)
+    {
+        options->secondsRequiredToStartPlayingAfterBufferUnderun = MIN(STK_DEFAULT_SECONDS_REQUIRED_TO_START_PLAYING_AFTER_BUFFER_UNDERRUN, options->bufferSizeInSeconds);
+    }
+}
+
+#define CHECK_STATUS_AND_RETURN(call) \
+	if ((status = (call))) \
+	{ \
+		[self unexpectedError:STKAudioPlayerErrorAudioSystemError]; \
+		return;\
+	}
+
+#define CHECK_STATUS_AND_RETURN_VALUE(call, value) \
+	if ((status = (call))) \
+	{ \
+		[self unexpectedError:STKAudioPlayerErrorAudioSystemError]; \
+		return value;\
+	}
+
 typedef enum
 {
 	STKAudioPlayerInternalStateInitialised = 0,
@@ -112,6 +150,14 @@ STKAudioPlayerInternalState;
 
 #pragma mark STKAudioPlayer
 
+static UInt32 maxFramesPerSlice = 4096;
+
+static AudioComponentDescription mixerDescription;
+static AudioComponentDescription nbandUnitDescription;
+static AudioComponentDescription outputUnitDescription;
+static AudioComponentDescription convertUnitDescription;
+static AudioStreamBasicDescription canonicalAudioStreamBasicDescription;
+
 @interface STKAudioPlayer()
 {
 	BOOL muted;
@@ -120,12 +166,32 @@ STKAudioPlayerInternalState;
     int readBufferSize;
     STKAudioPlayerInternalState internalState;
 	
+	Float32 volume;
 	Float32 peakPowerDb[2];
 	Float32 averagePowerDb[2];
 	
 	BOOL meteringEnabled;
+    BOOL equalizerOn;
+    BOOL equalizerEnabled;
     STKAudioPlayerOptions options;
-    AudioComponentInstance audioUnit;
+
+    NSMutableArray* converterNodes;
+
+	AUGraph audioGraph;
+    AUNode eqNode;
+	AUNode mixerNode;
+    AUNode outputNode;
+	
+	AUNode eqInputNode;
+	AUNode eqOutputNode;
+	AUNode mixerInputNode;
+	AUNode mixerOutputNode;
+	
+    AudioComponentInstance eqUnit;
+	AudioComponentInstance mixerUnit;
+	AudioComponentInstance outputUnit;
+		
+    UInt32 eqBandCount;
     
     UInt32 framesRequiredToStartPlaying;
     UInt32 framesRequiredToPlayAfterRebuffering;
@@ -137,6 +203,7 @@ STKAudioPlayerInternalState;
     NSMutableArray* bufferingQueue;
     
     OSSpinLock pcmBufferSpinLock;
+    OSSpinLock internalStateLock;
     volatile UInt32 pcmBufferTotalFrameCount;
     volatile UInt32 pcmBufferFrameStartIndex;
     volatile UInt32 pcmBufferUsedFrameCount;
@@ -146,7 +213,6 @@ STKAudioPlayerInternalState;
     AudioBufferList pcmAudioBufferList;
     AudioConverterRef audioConverterRef;
 
-    AudioStreamBasicDescription canonicalAudioStreamBasicDescription;
     AudioStreamBasicDescription audioConverterAudioStreamBasicDescription;
     
     BOOL discontinuous;
@@ -200,6 +266,60 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
 
 @implementation STKAudioPlayer
 
++(void) initialize
+{
+    convertUnitDescription = (AudioComponentDescription)
+    {
+        .componentManufacturer = kAudioUnitManufacturer_Apple,
+        .componentType = kAudioUnitType_FormatConverter,
+        .componentSubType = kAudioUnitSubType_AUConverter,
+        .componentFlags = 0,
+        .componentFlagsMask = 0
+	};
+    
+    const int bytesPerSample = sizeof(AudioSampleType);
+    
+    canonicalAudioStreamBasicDescription = (AudioStreamBasicDescription)
+    {
+        .mSampleRate = 44100.00,
+        .mFormatID = kAudioFormatLinearPCM,
+        .mFormatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagsNativeEndian | kAudioFormatFlagIsPacked,
+        .mFramesPerPacket = 1,
+        .mChannelsPerFrame = 2,
+        .mBytesPerFrame = bytesPerSample * 2 /*channelsPerFrame*/,
+        .mBitsPerChannel = 8 * bytesPerSample,
+        .mBytesPerPacket = (bytesPerSample * 2)
+    };
+	
+	outputUnitDescription = (AudioComponentDescription)
+	{
+		.componentType = kAudioUnitType_Output,
+#if TARGET_OS_IPHONE
+		.componentSubType = kAudioUnitSubType_RemoteIO,
+#else
+		.componentSubType = kAudioUnitSubType_DefaultOutput,
+#endif
+		.componentFlags = 0,
+		.componentFlagsMask = 0,
+		.componentManufacturer = kAudioUnitManufacturer_Apple
+	};
+	
+	mixerDescription = (AudioComponentDescription)
+	{
+		.componentType = kAudioUnitType_Mixer,
+		.componentSubType = kAudioUnitSubType_MultiChannelMixer,
+		.componentFlags = 0,
+		.componentFlagsMask = 0,
+		.componentManufacturer = kAudioUnitManufacturer_Apple
+	};
+    
+	nbandUnitDescription = (AudioComponentDescription)
+	{
+		.componentType = kAudioUnitType_Effect,
+		.componentSubType = kAudioUnitSubType_NBandEQ,
+		.componentManufacturer=kAudioUnitManufacturer_Apple
+	};
+}
 -(STKAudioPlayerOptions) options
 {
     return options;
@@ -212,16 +332,14 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
 
 -(void) setInternalState:(STKAudioPlayerInternalState)value
 {
-    if (value == internalState)
-    {
-        return;
-    }
-    
-    internalState = value;
-    
+    [self setInternalState:value ifInState:NULL];
+}
+
+-(void) setInternalState:(STKAudioPlayerInternalState)value ifInState:(BOOL(^)(STKAudioPlayerInternalState))ifInState
+{
     STKAudioPlayerState newState;
     
-    switch (internalState)
+    switch (value)
     {
         case STKAudioPlayerInternalStateInitialised:
             newState = STKAudioPlayerStateReady;
@@ -257,17 +375,44 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
             break;
     }
     
+    OSSpinLockLock(&internalStateLock);
+    
+    if (value == internalState)
+    {
+        OSSpinLockUnlock(&internalStateLock);
+        
+        return;
+    }
+    
+    if (ifInState != NULL)
+    {
+        if (!ifInState(self->internalState))
+        {
+            OSSpinLockUnlock(&internalStateLock);
+            
+            return;
+        }
+    }
+    
+    internalState = value;
+    
 	STKAudioPlayerState previousState = self.state;
 	
     if (newState != previousState)
     {
         self.state = newState;
         
+        OSSpinLockUnlock(&internalStateLock);
+        
         dispatch_async(dispatch_get_main_queue(), ^
         {
             [self.delegate audioPlayer:self stateChanged:self.state previousState:previousState];
         });
     }
+    else
+    {
+        OSSpinLockUnlock(&internalStateLock);
+    }
 }
 
 -(STKAudioPlayerStopReason) stopReason
@@ -295,45 +440,34 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
 
 -(id) init
 {
-    return [self initWithReadBufferSize:STK_DEFAULT_READ_BUFFER_SIZE andOptions:STKAudioPlayerOptionNone];
+    return [self initWithOptions:(STKAudioPlayerOptions){}];
 }
 
 -(id) initWithOptions:(STKAudioPlayerOptions)optionsIn
-{
-	return [self initWithReadBufferSize:STK_DEFAULT_READ_BUFFER_SIZE andOptions:optionsIn];
-}
-
--(id) initWithReadBufferSize:(int)readBufferSizeIn andOptions:(STKAudioPlayerOptions)optionsIn
 {
     if (self = [super init])
     {
         options = optionsIn;
-
-        const int bytesPerSample = sizeof(AudioSampleType);
 		
-        canonicalAudioStreamBasicDescription.mSampleRate = 44100.00;
-        canonicalAudioStreamBasicDescription.mFormatID = kAudioFormatLinearPCM;
-        canonicalAudioStreamBasicDescription.mFormatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagsNativeEndian | kAudioFormatFlagIsPacked;
-        canonicalAudioStreamBasicDescription.mFramesPerPacket = 1;
-        canonicalAudioStreamBasicDescription.mChannelsPerFrame = 2;
-        canonicalAudioStreamBasicDescription.mBytesPerFrame = bytesPerSample * canonicalAudioStreamBasicDescription.mChannelsPerFrame;
-        canonicalAudioStreamBasicDescription.mBitsPerChannel = 8 * bytesPerSample;
-        canonicalAudioStreamBasicDescription.mBytesPerPacket = canonicalAudioStreamBasicDescription.mBytesPerFrame * canonicalAudioStreamBasicDescription.mFramesPerPacket;
+		self->volume = 1.0;
+        self->equalizerEnabled = optionsIn.equalizerBandFrequencies[0] != 0;
+
+        PopulateOptionsWithDefault(&options);
         
-        framesRequiredToStartPlaying = canonicalAudioStreamBasicDescription.mSampleRate * STK_DEFAULT_SECONDS_REQUIRED_TO_START_PLAYING;
-        framesRequiredToPlayAfterRebuffering = canonicalAudioStreamBasicDescription.mSampleRate * STK_DEFAULT_PCM_BUFFER_SIZE_IN_SECONDS;
+        framesRequiredToStartPlaying = canonicalAudioStreamBasicDescription.mSampleRate * options.secondsRequiredToStartPlaying;
+        framesRequiredToPlayAfterRebuffering = canonicalAudioStreamBasicDescription.mSampleRate * options.secondsRequiredToStartPlayingAfterBufferUnderun;
         
         pcmAudioBuffer = &pcmAudioBufferList.mBuffers[0];
         
         pcmAudioBufferList.mNumberBuffers = 1;
-        pcmAudioBufferList.mBuffers[0].mDataByteSize = (canonicalAudioStreamBasicDescription.mSampleRate * STK_DEFAULT_PCM_BUFFER_SIZE_IN_SECONDS) * canonicalAudioStreamBasicDescription.mBytesPerFrame;
+        pcmAudioBufferList.mBuffers[0].mDataByteSize = (canonicalAudioStreamBasicDescription.mSampleRate * options.bufferSizeInSeconds) * canonicalAudioStreamBasicDescription.mBytesPerFrame;
         pcmAudioBufferList.mBuffers[0].mData = (void*)calloc(pcmAudioBuffer->mDataByteSize, 1);
         pcmAudioBufferList.mBuffers[0].mNumberChannels = 2;
 		
         pcmBufferFrameSizeInBytes = canonicalAudioStreamBasicDescription.mBytesPerFrame;
         pcmBufferTotalFrameCount = pcmAudioBuffer->mDataByteSize / pcmBufferFrameSizeInBytes;
         
-        readBufferSize = readBufferSizeIn;
+        readBufferSize = options.readBufferSize;
         readBuffer = calloc(sizeof(UInt8), readBufferSize);
         
         pthread_mutexattr_t attr;
@@ -355,7 +489,7 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
         bufferingQueue = [[NSMutableArray alloc] init];
 
 		[self resetPcmBuffers];
-        [self createAudioUnit];
+        [self createAudioGraph];
         [self createPlaybackThread];
     }
     
@@ -388,11 +522,17 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
         AudioConverterDispose(audioConverterRef);
     }
     
-    if (audioUnit)
+    if (outputUnit)
     {
-        AudioComponentInstanceDispose(audioUnit);
+        AudioComponentInstanceDispose(outputUnit);
     }
     
+    if (audioGraph)
+    {
+        AUGraphUninitialize(audioGraph);
+        AUGraphClose(audioGraph);
+    }
+	
     pthread_mutex_destroy(&playerMutex);
     pthread_mutex_destroy(&mainThreadSyncCallMutex);
     pthread_cond_destroy(&playerThreadReadyCondition);
@@ -732,7 +872,7 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
 
 -(Float64) currentTimeInFrames
 {
-    if (audioUnit == nil)
+    if (audioGraph == nil)
     {
         return 0;
     }
@@ -932,7 +1072,8 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
         }
         
         [self processFinishPlayingIfAnyAndPlayingNext:currentlyPlayingEntry withNext:entry];
-        [self startAudioUnit];
+        
+        [self startAudioGraph];
     }
     else
     {
@@ -1111,7 +1252,7 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
                 [currentlyReadingEntry.dataSource unregisterForEvents];
             }
             
-            if (self->options & STKAudioPlayerOptionFlushQueueOnSeek)
+            if (self->options.flushQueueOnSeek)
             {
                 self.internalState = STKAudioPlayerInternalStateWaitingForDataAfterSeek;
                 [self setCurrentlyReadingEntry:currentlyPlayingEntry andStartPlaying:YES clearQueue:YES];
@@ -1286,7 +1427,7 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
     
     self.internalState = STKAudioPlayerInternalStateWaitingForDataAfterSeek;
     
-    if (audioUnit)
+    if (audioGraph)
     {
         [self resetPcmBuffers];
     }
@@ -1430,9 +1571,9 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
             self.stateBeforePaused = self.internalState;
             self.internalState = STKAudioPlayerInternalStatePaused;
             
-            if (audioUnit)
+            if (audioGraph)
             {
-                error = AudioOutputUnitStop(audioUnit);
+                error = AUGraphStop(audioGraph);
                 
                 if (error)
                 {
@@ -1465,9 +1606,9 @@ static void AudioFileStreamPacketsProc(void* clientData, UInt32 numberBytes, UIn
                 [self resetPcmBuffers];
             }
 
-            if (audioUnit != nil)
+            if (audioGraph != nil)
             {
-                error = AudioOutputUnitStart(audioUnit);
+				error = AUGraphStart(audioGraph);
                 
                 if (error)
                 {
@@ -1722,88 +1863,262 @@ static BOOL GetHardwareCodecClassDesc(UInt32 formatId, AudioClassDescription* cl
     }
 }
 
--(void) createAudioUnit
+-(void) createOutputUnit
 {
-    pthread_mutex_lock(&playerMutex);
-    
-    OSStatus status;
-    AudioComponentDescription desc;
-    
-    desc.componentType = kAudioUnitType_Output;
-#if TARGET_OS_IPHONE
-    desc.componentSubType = kAudioUnitSubType_RemoteIO;
-#else
-	desc.componentSubType = kAudioUnitSubType_DefaultOutput;
-#endif
-    desc.componentFlags = 0;
-    desc.componentFlagsMask = 0;
-    desc.componentManufacturer = kAudioUnitManufacturer_Apple;
-    
-    AudioComponent component = AudioComponentFindNext(NULL, &desc);
-    
-    status = AudioComponentInstanceNew(component, &audioUnit);
-    
-    if (status)
-    {
-        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
-        
-        return;
-    }
-    
+	OSStatus status;
+	
+	CHECK_STATUS_AND_RETURN(AUGraphAddNode(audioGraph, &outputUnitDescription, &outputNode));
+	CHECK_STATUS_AND_RETURN(AUGraphNodeInfo(audioGraph, outputNode, &outputUnitDescription, &outputUnit));
+	
 #if TARGET_OS_IPHONE
     UInt32 flag = 1;
-	status = AudioUnitSetProperty(audioUnit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output, kOutputBus, &flag, sizeof(flag));
-    
-    if (status)
-    {
-        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
-        
-        return;
-    }
+	
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(outputUnit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output, kOutputBus, &flag, sizeof(flag)));
+
+	flag = 0;
+	
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(outputUnit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Input, kInputBus, &flag, sizeof(flag)));
 #endif
     
-    status = AudioUnitSetProperty(audioUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, kOutputBus, &canonicalAudioStreamBasicDescription, sizeof(canonicalAudioStreamBasicDescription));
-    
-    if (status)
-    {
-        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
-        
-        return;
-    }
-    
-    AURenderCallbackStruct callbackStruct;
-    
-    callbackStruct.inputProc = OutputRenderCallback;
-    callbackStruct.inputProcRefCon = (__bridge void*)self;
-
-    status = AudioUnitSetProperty(audioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, kOutputBus, &callbackStruct, sizeof(callbackStruct));
-    
-    if (status)
-    {
-        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
-        
-        return;
-    }
- 
-    status = AudioUnitInitialize(audioUnit);
-    
-    if (status)
-    {
-        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
-        
-        return;
-    }
-    
-    pthread_mutex_unlock(&playerMutex);
+    CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(outputUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, kOutputBus, &canonicalAudioStreamBasicDescription, sizeof(canonicalAudioStreamBasicDescription)));
 }
 
--(BOOL) startAudioUnit
+-(void) createMixerUnit
+{
+	OSStatus status;
+	
+	if (!self.options.enableVolumeMixer)
+	{
+		return;
+	}
+	
+	CHECK_STATUS_AND_RETURN(AUGraphAddNode(audioGraph, &mixerDescription, &mixerNode));
+	CHECK_STATUS_AND_RETURN(AUGraphNodeInfo(audioGraph, mixerNode, &mixerDescription, &mixerUnit));
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(mixerUnit, kAudioUnitProperty_MaximumFramesPerSlice, kAudioUnitScope_Global, 0, &maxFramesPerSlice, sizeof(maxFramesPerSlice)));
+	
+	UInt32 busCount = 1;
+	
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(mixerUnit, kAudioUnitProperty_ElementCount, kAudioUnitScope_Input, 0, &busCount, sizeof(busCount)));
+	
+	Float64 graphSampleRate = 44100.0;
+	
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(mixerUnit, kAudioUnitProperty_SampleRate, kAudioUnitScope_Output, 0, &graphSampleRate, sizeof(graphSampleRate)));
+	CHECK_STATUS_AND_RETURN(AudioUnitSetParameter(mixerUnit, kMultiChannelMixerParam_Volume, kAudioUnitScope_Input, 0, 1.0, 0));
+}
+
+-(void) createEqUnit
+{
+#if TARGET_OS_MAC && MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_9
+    return;
+#else
+	OSStatus status;
+    
+	if (self->options.equalizerBandFrequencies[0] == 0)
+    {
+		return;
+	}
+	
+	CHECK_STATUS_AND_RETURN(AUGraphAddNode(audioGraph, &nbandUnitDescription, &eqNode));
+	CHECK_STATUS_AND_RETURN(AUGraphNodeInfo(audioGraph, eqNode, NULL, &eqUnit));
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(eqUnit, kAudioUnitProperty_MaximumFramesPerSlice, kAudioUnitScope_Global, 0, &maxFramesPerSlice, sizeof(maxFramesPerSlice)));
+	
+	while (self->options.equalizerBandFrequencies[eqBandCount] != 0)
+	{
+		eqBandCount++;
+	}
+	
+	CHECK_STATUS_AND_RETURN(AudioUnitSetProperty(eqUnit, kAUNBandEQProperty_NumberOfBands, kAudioUnitScope_Global, 0, &eqBandCount, sizeof(eqBandCount)));
+	
+	for (int i = 0; i < eqBandCount; i++)
+	{
+		CHECK_STATUS_AND_RETURN(AudioUnitSetParameter(eqUnit, kAUNBandEQParam_Frequency + i, kAudioUnitScope_Global, 0, (AudioUnitParameterValue)self->options.equalizerBandFrequencies[i], 0));
+	}
+	
+	for (int i = 0; i < eqBandCount; i++)
+	{
+		CHECK_STATUS_AND_RETURN(AudioUnitSetParameter(eqUnit, kAUNBandEQParam_BypassBand + i, kAudioUnitScope_Global, 0, (AudioUnitParameterValue)0, 0));
+	}
+#endif
+}
+
+-(void) setGain:(float)gain forEqualizerBand:(int)bandIndex
+{
+	if (!eqUnit)
+	{
+		return;
+	}
+    
+    OSStatus status;
+	
+	CHECK_STATUS_AND_RETURN(AudioUnitSetParameter(eqUnit, kAUNBandEQParam_Gain + bandIndex, kAudioUnitScope_Global, 0, gain, 0));
+}
+
+-(AUNode) createConverterNode:(AudioStreamBasicDescription)srcFormat desFormat:(AudioStreamBasicDescription)desFormat
+{
+	OSStatus status;
+	AUNode convertNode;
+	AudioComponentInstance convertUnit;
+	
+	CHECK_STATUS_AND_RETURN_VALUE(AUGraphAddNode(audioGraph, &convertUnitDescription, &convertNode), 0);
+	CHECK_STATUS_AND_RETURN_VALUE(status = AUGraphNodeInfo(audioGraph, convertNode, &mixerDescription, &convertUnit), 0);
+	CHECK_STATUS_AND_RETURN_VALUE(AudioUnitSetProperty(convertUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &srcFormat, sizeof(srcFormat)), 0);
+  	CHECK_STATUS_AND_RETURN_VALUE(AudioUnitSetProperty(convertUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Output, 0, &desFormat, sizeof(desFormat)), 0);
+	CHECK_STATUS_AND_RETURN_VALUE(AudioUnitSetProperty(convertUnit, kAudioUnitProperty_MaximumFramesPerSlice, kAudioUnitScope_Global, 0, &maxFramesPerSlice, sizeof(maxFramesPerSlice)), 0);
+    
+    [converterNodes addObject:@(convertNode)];
+
+	return convertNode;
+}
+
+-(void) connectNodes:(AUNode)srcNode desNode:(AUNode)desNode srcUnit:(AudioComponentInstance)srcUnit desUnit:(AudioComponentInstance)desUnit
+{
+    OSStatus status;
+    BOOL addConverter = NO;
+    AudioStreamBasicDescription srcFormat, desFormat;
+    UInt32 size = sizeof(AudioStreamBasicDescription);
+    
+    CHECK_STATUS_AND_RETURN(AudioUnitGetProperty(srcUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Output, 0, &srcFormat, &size));
+    CHECK_STATUS_AND_RETURN(AudioUnitGetProperty(desUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &desFormat, &size));
+    
+    addConverter = memcmp(&srcFormat, &desFormat, sizeof(srcFormat)) != 0;
+    
+    if (addConverter)
+    {
+        status = AudioUnitSetProperty(desUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &srcFormat, sizeof(srcFormat));
+        
+        addConverter = status != 0;
+    }
+    
+    if (addConverter) 
+    {
+        AUNode convertNode = [self createConverterNode:srcFormat desFormat:desFormat];
+        
+        CHECK_STATUS_AND_RETURN(AUGraphConnectNodeInput(audioGraph, srcNode, 0, convertNode, 0));
+		CHECK_STATUS_AND_RETURN(AUGraphConnectNodeInput(audioGraph, convertNode, 0, desNode, 0));
+    }
+    else
+    {
+		CHECK_STATUS_AND_RETURN(AUGraphConnectNodeInput(audioGraph, srcNode, 0, desNode, 0));
+    }
+}
+
+-(void) setOutputCallbackForFirstNode:(AUNode)firstNode firstUnit:(AudioComponentInstance)firstUnit
+{
+	OSStatus status;
+	AURenderCallbackStruct callbackStruct;
+	
+    callbackStruct.inputProc = OutputRenderCallback;
+    callbackStruct.inputProcRefCon = (__bridge void*)self;
+	
+    status = AudioUnitSetProperty(firstUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &canonicalAudioStreamBasicDescription, sizeof(canonicalAudioStreamBasicDescription));
+	
+	if (status)
+	{
+		AudioStreamBasicDescription format;
+		UInt32 size = sizeof(format);
+		
+		CHECK_STATUS_AND_RETURN(AudioUnitGetProperty(firstUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &format, &size));
+		
+		AUNode converterNode = [self createConverterNode:canonicalAudioStreamBasicDescription desFormat:format];
+		
+        CHECK_STATUS_AND_RETURN(AUGraphSetNodeInputCallback(audioGraph, converterNode, 0, &callbackStruct));
+		
+		status = AUGraphConnectNodeInput(audioGraph, converterNode, 0, firstNode, 0);
+	}
+	else
+	{
+		CHECK_STATUS_AND_RETURN(AUGraphSetNodeInputCallback(audioGraph, firstNode, 0, &callbackStruct));
+	}
+}
+
+-(void) createAudioGraph
+{
+    OSStatus status;
+    converterNodes = [[NSMutableArray alloc] init];
+    
+	CHECK_STATUS_AND_RETURN(NewAUGraph(&audioGraph));
+	CHECK_STATUS_AND_RETURN(AUGraphOpen(audioGraph));
+	
+	[self createEqUnit];
+	[self createMixerUnit];
+	[self createOutputUnit];
+    
+    [self connectGraph];
+	
+	CHECK_STATUS_AND_RETURN(AUGraphInitialize(audioGraph));
+	
+	self.volume = self->volume;
+}
+
+-(void) connectGraph
+{
+    OSStatus status;
+    NSMutableArray* nodes = [[NSMutableArray alloc] init];
+    NSMutableArray* units = [[NSMutableArray alloc] init];
+    
+    AUGraphClearConnections(audioGraph);
+    
+    for (NSNumber* converterNode in converterNodes)
+    {
+        status = AUGraphRemoveNode(audioGraph, (AUNode)converterNode.intValue);
+    }
+    
+    [converterNodes removeAllObjects];
+
+    if (eqNode)
+    {
+        if (self->equalizerEnabled)
+        {
+            [nodes addObject:@(eqNode)];
+            [units addObject:[NSValue valueWithPointer:eqUnit]];
+            
+            self->equalizerOn = YES;
+        }
+        else
+        {
+            self->equalizerOn = NO;
+        }
+	}
+    else
+    {
+        self->equalizerOn = NO;
+    }
+    
+    if (mixerNode)
+    {
+        [nodes addObject:@(mixerNode)];
+        [units addObject:[NSValue valueWithPointer:mixerUnit]];
+    }
+	
+    if (outputNode)
+    {
+        [nodes addObject:@(outputNode)];
+        [units addObject:[NSValue valueWithPointer:outputUnit]];
+    }
+    
+	[self setOutputCallbackForFirstNode:(AUNode)[[nodes objectAtIndex:0] intValue] firstUnit:(AudioComponentInstance)[[units objectAtIndex:0] pointerValue]];
+    
+	for (int i = 0; i < nodes.count - 1; i++)
+    {
+        AUNode srcNode = [[nodes objectAtIndex:i] intValue];
+        AUNode desNode = [[nodes objectAtIndex:i + 1] intValue];
+        AudioComponentInstance srcUnit = (AudioComponentInstance)[[units objectAtIndex:i] pointerValue];
+        AudioComponentInstance desUnit = (AudioComponentInstance)[[units objectAtIndex:i + 1] pointerValue];
+        
+        [self connectNodes:srcNode desNode:desNode srcUnit:srcUnit desUnit:desUnit];
+    }
+}
+
+-(BOOL) startAudioGraph
 {
     OSStatus status;
     
 	[self resetPcmBuffers];
+    
+    Boolean isRunning;
 	
-    status = AudioOutputUnitStart(audioUnit);
+    
+    status = AUGraphIsRunning(audioGraph, &isRunning);
     
     if (status)
     {
@@ -1812,6 +2127,20 @@ static BOOL GetHardwareCodecClassDesc(UInt32 formatId, AudioClassDescription* cl
         return NO;
     }
     
+    if (isRunning)
+    {
+        return NO;
+    }
+	
+    status = AUGraphStart(audioGraph);
+    
+    if (status)
+    {
+        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
+        
+        return NO;
+    }
+	
     return YES;
 }
 
@@ -1819,7 +2148,7 @@ static BOOL GetHardwareCodecClassDesc(UInt32 formatId, AudioClassDescription* cl
 {
 	OSStatus status;
 	
-	if (!audioUnit)
+	if (!audioGraph)
     {
         stopReason = stopReasonIn;
         self.internalState = STKAudioPlayerInternalStateStopped;
@@ -1827,17 +2156,28 @@ static BOOL GetHardwareCodecClassDesc(UInt32 formatId, AudioClassDescription* cl
         return;
     }
     
-    status = AudioOutputUnitStop(audioUnit);
-	
-	[self resetPcmBuffers];
+    Boolean isRunning;
+    
+    status = AUGraphIsRunning(audioGraph, &isRunning);
     
     if (status)
     {
         [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
-        
+    }
+    else if (!isRunning)
+    {
         return;
     }
     
+    status = AUGraphStop(audioGraph);
+	
+    if (status)
+    {
+        [self unexpectedError:STKAudioPlayerErrorAudioSystemError];
+    }
+    
+    [self resetPcmBuffers];
+    
     stopReason = stopReasonIn;
     self.internalState = STKAudioPlayerInternalStateStopped;
 }
@@ -2126,19 +2466,11 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
     UInt32 frameSizeInBytes = audioPlayer->pcmBufferFrameSizeInBytes;
     UInt32 used = audioPlayer->pcmBufferUsedFrameCount;
     UInt32 start = audioPlayer->pcmBufferFrameStartIndex;
+    STKAudioPlayerInternalState state = audioPlayer->internalState;
     UInt32 end = (audioPlayer->pcmBufferFrameStartIndex + audioPlayer->pcmBufferUsedFrameCount) % audioPlayer->pcmBufferTotalFrameCount;
     BOOL signal = audioPlayer->waiting && used < audioPlayer->pcmBufferTotalFrameCount / 2;
 	NSArray* frameFilters = audioPlayer->frameFilters;
     
-    STKAudioPlayerInternalState state = audioPlayer.internalState;
-    
-	if (state == STKAudioPlayerInternalStatePendingNext)
-    {
-        OSSpinLockUnlock(&audioPlayer->pcmBufferSpinLock);
-        
-        return 0;
-    }
-
 	if (entry)
 	{
 		if (state == STKAudioPlayerInternalStateWaitingForData)
@@ -2158,9 +2490,23 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
 		}
 		else if (state == STKAudioPlayerInternalStateRebuffering)
 		{
-			int64_t framesRequiredToStartPlaying = audioPlayer->framesRequiredToStartPlaying;
+			int64_t framesRequiredToStartPlaying = audioPlayer->framesRequiredToPlayAfterRebuffering;
 			
-			if (audioPlayer->currentlyPlayingEntry->lastFrameQueued >= 0)
+			if (entry->lastFrameQueued >= 0)
+			{
+				framesRequiredToStartPlaying = MIN(framesRequiredToStartPlaying, entry->lastFrameQueued - entry->framesQueued);
+			}
+			
+			if (used < framesRequiredToStartPlaying)
+			{
+				waitForBuffer = YES;
+			}
+		}
+		else if (state == STKAudioPlayerInternalStateWaitingForDataAfterSeek)
+		{
+			int64_t framesRequiredToStartPlaying = inNumberFrames;
+			
+			if (entry->lastFrameQueued >= 0)
 			{
 				framesRequiredToStartPlaying = MIN(framesRequiredToStartPlaying, entry->lastFrameQueued - entry->framesQueued);
 			}
@@ -2176,7 +2522,7 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
     
     UInt32 totalFramesCopied = 0;
     
-    if (used > 0 && !waitForBuffer && entry != nil)
+    if (used > 0 && !waitForBuffer && entry != nil && ((state & STKAudioPlayerInternalStateRunning) && state != STKAudioPlayerInternalStatePaused))
     {
         if (state == STKAudioPlayerInternalStateWaitingForData)
         {
@@ -2254,7 +2600,10 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
             OSSpinLockUnlock(&audioPlayer->pcmBufferSpinLock);
         }
         
-        audioPlayer.internalState = STKAudioPlayerInternalStatePlaying;
+        [audioPlayer setInternalState:STKAudioPlayerInternalStatePlaying ifInState:^BOOL(STKAudioPlayerInternalState state)
+        {
+            return (state & STKAudioPlayerInternalStateRunning) && state != STKAudioPlayerInternalStatePaused;
+        }];
     }
     
     if (totalFramesCopied < inNumberFrames)
@@ -2267,14 +2616,17 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
         {
             // Buffering
             
-            audioPlayer.internalState = STKAudioPlayerInternalStateRebuffering;
+            [audioPlayer setInternalState:STKAudioPlayerInternalStateRebuffering ifInState:^BOOL(STKAudioPlayerInternalState state)
+            {
+                 return (state & STKAudioPlayerInternalStateRunning) && state != STKAudioPlayerInternalStatePaused;
+            }];
         }
     }
 
 	if (frameFilters)
 	{
 		NSUInteger count = frameFilters.count;
-		AudioStreamBasicDescription asbd = audioPlayer->canonicalAudioStreamBasicDescription;
+		AudioStreamBasicDescription asbd = canonicalAudioStreamBasicDescription;
 		
 		for (int i = 0; i < count; i++)
 		{
@@ -2283,6 +2635,17 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
 			entry->filter(asbd.mChannelsPerFrame, asbd.mBytesPerFrame, inNumberFrames, ioData->mBuffers[0].mData);
 		}
 	}
+    
+    if (audioPlayer->equalizerEnabled != audioPlayer->equalizerOn)
+    {
+        Boolean isUpdated;
+        
+        [audioPlayer connectGraph];
+        
+        AUGraphUpdate(audioPlayer->audioGraph, &isUpdated);
+        
+        isUpdated = isUpdated;
+    }
 	
     if (entry == nil)
     {
@@ -2636,4 +2999,43 @@ static OSStatus OutputRenderCallback(void* inRefCon, AudioUnitRenderActionFlags*
 	pthread_mutex_unlock(&self->playerMutex);
 }
 
+#pragma mark Volume
+
+-(void) setVolume:(Float32)value;
+{
+	self->volume = value;
+	
+#if (TARGET_OS_IPHONE)
+	if (self->mixerNode)
+	{
+		AudioUnitSetParameter(self->mixerUnit, kMultiChannelMixerParam_Volume, kAudioUnitScope_Output, 0, self->volume, 0);
+	}
+#else
+	if (self->mixerNode)
+	{
+		AudioUnitSetParameter(self->mixerUnit, kMultiChannelMixerParam_Volume, kAudioUnitScope_Output, 0, self->volume, 0);
+	}
+	else
+	{
+		AudioUnitSetParameter(outputUnit, kHALOutputParam_Volume, kAudioUnitScope_Output, kOutputBus, self->volume, 0);
+	}
+#endif
+}
+
+-(Float32) volume
+{
+	return self->volume;
+}
+
+-(BOOL) equalizerEnabled
+{
+    return self->equalizerEnabled;
+}
+
+-(void) setEqualizerEnabled:(BOOL)value
+{
+    self->equalizerEnabled = value;
+}
+
+
 @end

StreamingKit/StreamingKit/STKHTTPDataSource.m

@@ -138,15 +138,22 @@
 
 -(void) dataAvailable
 {
+    if (stream == NULL) {
+        return;
+    }
+    
 	if (self.httpStatusCode == 0)
 	{
 		CFTypeRef response = CFReadStreamCopyProperty(stream, kCFStreamPropertyHTTPResponseHeader);
         
-        httpHeaders = (__bridge_transfer NSDictionary*)CFHTTPMessageCopyAllHeaderFields((CFHTTPMessageRef)response);
-        
-        self.httpStatusCode = CFHTTPMessageGetResponseStatusCode((CFHTTPMessageRef)response);
-        
-        CFRelease(response);
+        if (response)
+        {
+            httpHeaders = (__bridge_transfer NSDictionary*)CFHTTPMessageCopyAllHeaderFields((CFHTTPMessageRef)response);
+            
+            self.httpStatusCode = CFHTTPMessageGetResponseStatusCode((CFHTTPMessageRef)response);
+            
+            CFRelease(response);
+        }
 		
 		if (self.httpStatusCode == 200)
 		{