diff --git a/e2e/remote-agent/main.go b/e2e/remote-agent/main.go
index 00f5207d..47387f10 100644
--- a/e2e/remote-agent/main.go
+++ b/e2e/remote-agent/main.go
@@ -62,7 +62,7 @@ type InputEvent struct {
 	Time   int64  `json:"time_ms"`
 	Type   string `json:"type"`             // "key_press", "key_release", "key_repeat", "mouse_move_rel", "mouse_move_abs", "mouse_button"
 	Code   uint16 `json:"code"`             // Linux key code or axis
-	Value  int32  `json:"value,omitempty"`   // Key: 0/1/2, Mouse: delta or position
+	Value  int32  `json:"value"`             // Key: 0/1/2, Mouse: delta or position
 	X      int32  `json:"x"`                 // Mouse X (for move events)
 	Y      int32  `json:"y"`                 // Mouse Y (for move events)
 	Device string `json:"device,omitempty"`  // Source device name
diff --git a/ui/e2e/remote-agent/ra-all.spec.ts b/ui/e2e/remote-agent/ra-all.spec.ts
index 956d21c2..5043f346 100644
--- a/ui/e2e/remote-agent/ra-all.spec.ts
+++ b/ui/e2e/remote-agent/ra-all.spec.ts
@@ -901,6 +901,54 @@ test.describe("Remote Host Agent", () => {
     }
   });
 
+  test("mouse: multi-button combinations (hold left, press right)", async () => {
+    const BTN_LEFT = 0x110; // 272
+    const BTN_RIGHT = 0x111; // 273
+
+    // Move mouse to a stable position first
+    await sendAbsMouseMove(sharedPage, 16384, 16384);
+    await new Promise(r => setTimeout(r, 100));
+
+    let successes = 0;
+    const attempts = 20;
+
+    for (let i = 0; i < attempts; i++) {
+      await agent!.clearMouseEvents();
+
+      // Press left button (buttons bitmask: 1 = left)
+      await sendAbsMouseMove(sharedPage, 16384, 16384, 1);
+      await new Promise(r => setTimeout(r, 100));
+
+      // While holding left, press right button (buttons bitmask: 3 = left + right)
+      await sendAbsMouseMove(sharedPage, 16384, 16384, 3);
+      await new Promise(r => setTimeout(r, 100));
+
+      // Release right button, left still held (buttons bitmask: 1 = left)
+      await sendAbsMouseMove(sharedPage, 16384, 16384, 1);
+      await new Promise(r => setTimeout(r, 100));
+
+      // Release all buttons (buttons bitmask: 0)
+      await sendAbsMouseMove(sharedPage, 16384, 16384, 0);
+      await new Promise(r => setTimeout(r, 150));
+
+      const events = await agent!.getMouseEvents();
+      const buttonEvents = events.filter(ev => ev.type === "mouse_button");
+
+      // We expect to see button events for both left and right buttons
+      const leftPress = buttonEvents.find(ev => ev.code === BTN_LEFT && ev.value === 1);
+      const rightPress = buttonEvents.find(ev => ev.code === BTN_RIGHT && ev.value === 1);
+      const rightRelease = buttonEvents.find(ev => ev.code === BTN_RIGHT && ev.value === 0);
+      const leftRelease = buttonEvents.find(ev => ev.code === BTN_LEFT && ev.value === 0);
+
+      if (leftPress && rightPress && rightRelease && leftRelease) {
+        successes++;
+      }
+    }
+
+    // All attempts must succeed — button state changes must be reliably delivered
+    expect(successes, `Multi-button succeeded ${successes}/${attempts} times`).toBe(attempts);
+  });
+
   // ═══════════════════════════════════════════
   // MOUSE: BLUR DOES NOT JUMP TO TOP-LEFT (#392)
   // ═══════════════════════════════════════════
diff --git a/ui/e2e/remote-agent/remote-agent.ts b/ui/e2e/remote-agent/remote-agent.ts
index 9e7d1241..eb7d63c8 100644
--- a/ui/e2e/remote-agent/remote-agent.ts
+++ b/ui/e2e/remote-agent/remote-agent.ts
@@ -498,11 +498,9 @@ export class RemoteAgent {
 
   /**
    * Ensure the remote agent is running on the target host.
-   * If the agent isn't responding, build (if needed) and deploy it via SSH.
+   * Always rebuilds from source when it has changed and redeploys.
    */
   async ensureDeployed(sshTarget?: string): Promise<void> {
-    if (await this.health()) return;
-
     const host = this.baseUrl.replace(/^https?:\/\//, "").replace(/:\d+$/, "");
     const port = parseInt(this.baseUrl.replace(/.*:/, ""), 10);
     const target = sshTarget ?? process.env.JETKVM_REMOTE_HOST ?? `tony@${host}`;
@@ -512,13 +510,18 @@ export class RemoteAgent {
     const binary = path.join(agentDir, "remote-agent");
     const goSource = path.join(agentDir, "main.go");
 
-    if (!fs.existsSync(binary)) {
-      if (!fs.existsSync(goSource)) {
-        throw new Error(
-          `Remote agent source not found at ${goSource}. ` +
-            `Restore it with: git checkout e2e-remote-host-agent -- e2e/remote-agent/`,
-        );
-      }
+    if (!fs.existsSync(goSource)) {
+      throw new Error(
+        `Remote agent source not found at ${goSource}. ` +
+          `Restore it with: git checkout e2e-remote-host-agent -- e2e/remote-agent/`,
+      );
+    }
+
+    // Rebuild if source is newer than binary (or binary doesn't exist)
+    const needsBuild =
+      !fs.existsSync(binary) || fs.statSync(goSource).mtimeMs > fs.statSync(binary).mtimeMs;
+
+    if (needsBuild) {
       console.log("[remote-agent] Building remote-agent binary...");
       execSync("GOOS=linux GOARCH=amd64 go build -o remote-agent .", {
         cwd: agentDir,
@@ -526,9 +529,13 @@ export class RemoteAgent {
       });
     }
 
-    console.log(`[remote-agent] Deploying to ${target}...`);
+    // Skip deploy only when the binary hasn't changed and the agent is already running
+    if (!needsBuild && (await this.health())) return;
+
     const sshOpts =
       "-o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o ConnectTimeout=30 -o ServerAliveInterval=5 -o ServerAliveCountMax=3";
+
+    console.log(`[remote-agent] Deploying to ${target}...`);
     execSync(`scp ${sshOpts} "${binary}" ${target}:/tmp/remote-agent`, { stdio: "inherit" });
 
     console.log(`[remote-agent] Starting on port ${port}...`);
diff --git a/ui/src/hooks/useHidRpc.ts b/ui/src/hooks/useHidRpc.ts
index 76267e55..ae3055c5 100644
--- a/ui/src/hooks/useHidRpc.ts
+++ b/ui/src/hooks/useHidRpc.ts
@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useMemo } from "react";
+import { useCallback, useEffect, useMemo, useRef } from "react";
 import { Logger } from "tslog";
 
 import { useRTCStore } from "@hooks/stores";
@@ -247,10 +247,20 @@ export function useHidRpc(onHidRpcMessage?: (payload: RpcMessage) => void) {
     [sendMessage],
   );
 
+  const lastAbsButtons = useRef(0);
+
   const reportAbsMouseEvent = useCallback(
     (x: number, y: number, buttons: number) => {
+      const buttonsChanged = buttons !== lastAbsButtons.current;
+      lastAbsButtons.current = buttons;
+
       sendMessage(new PointerReportMessage(x, y, buttons), {
-        useUnreliableChannel: true,
+        // Use the reliable channel for button state changes to guarantee delivery.
+        // Movement-only events use the unreliable channel for lower latency;
+        // lost movement packets self-correct via subsequent mousemove events,
+        // but button-only changes (pointerdown/pointerup without movement) have
+        // no such redundancy and must not be dropped.
+        useUnreliableChannel: !buttonsChanged,
       });
     },
     [sendMessage],