Remove timeout and empty frame processing in Audio Source (#467)

* init

* update

* changeset

* format

Author: Shubhrakanti

.changeset/shiny-flies-cough.md

@@ -0,0 +1,5 @@
+---
+'@livekit/rtc-node': patch
+---
+
+bugfix: no more negative timeouts being set on AudioSource

packages/livekit-rtc/src/audio_source.ts

@@ -99,13 +99,19 @@ export class AudioSource {
       this.lastCapture = 0;
       this.currentQueueSize = 0;
       this.promise = this.newPromise();
+      this.timeout = undefined;
     });
   }
 
   async captureFrame(frame: AudioFrame) {
     if (this.closed) {
       throw new Error('AudioSource is closed');
     }
+
+    if (frame.samplesPerChannel === 0) {
+      return;
+    }
+
     const now = Number(process.hrtime.bigint() / BigInt(1000000));
     const elapsed = this.lastCapture === 0 ? 0 : now - this.lastCapture;
     const frameDurationMs = (frame.samplesPerChannel / frame.sampleRate) * 1000;
@@ -117,9 +123,7 @@ export class AudioSource {
       clearTimeout(this.timeout);
     }
 
-    // remove 50ms to account for processing time
-    // (e.g. using wait_for_playout for very small chunks)
-    this.timeout = setTimeout(this.release, this.currentQueueSize - 50);
+    this.timeout = setTimeout(this.release, this.currentQueueSize);
 
     const req = new CaptureAudioFrameRequest({
       sourceHandle: this.ffiHandle.handle,