fix(audio-levels): Reset audio level to 0 when remote user is muted.

When using getSynchornizationSources on the audio receiver to gather audio levels for remote tracks, browser reports last known audio levels even when the remote user is audio muted, we need to reset the value to zero here so that the audio levels are cleared.

modules/RTC/JitsiTrack.js

@@ -424,31 +424,32 @@ export default class JitsiTrack extends EventEmitter {
      * peerconnection (see /modules/statistics/LocalStatsCollector.js).
      */
     setAudioLevel(audioLevel, tpc) {
-        // The receiver seems to be reporting audio level immediately after the
-        // remote user has muted, so do not set the audio level on the track
-        // if it is muted.
-        if (browser.supportsReceiverStats()
-            && !this.isLocalAudioTrack()
-            && this.isWebRTCTrackMuted()) {
-            return;
+        let newAudioLevel = audioLevel;
+
+        // When using getSynchornizationSources on the audio receiver to gather audio levels for
+        // remote tracks, browser reports last known audio levels even when the remote user is
+        // audio muted, we need to reset the value to zero here so that the audio levels are cleared.
+        // Remote tracks have the tpc info present while local tracks do not.
+        if (browser.supportsReceiverStats() && typeof tpc !== 'undefined' && this.isMuted()) {
+            newAudioLevel = 0;
         }
 
-        if (this.audioLevel !== audioLevel) {
-            this.audioLevel = audioLevel;
+        if (this.audioLevel !== newAudioLevel) {
+            this.audioLevel = newAudioLevel;
             this.emit(
                 JitsiTrackEvents.TRACK_AUDIO_LEVEL_CHANGED,
-                audioLevel,
+                newAudioLevel,
                 tpc);
 
         // LocalStatsCollector reports a value of 0.008 for muted mics
         // and a value of 0 when there is no audio input.
         } else if (this.audioLevel === 0
-            && audioLevel === 0
+            && newAudioLevel === 0
             && this.isLocal()
             && !this.isWebRTCTrackMuted()) {
             this.emit(
                 JitsiTrackEvents.NO_AUDIO_INPUT,
-                audioLevel);
+                newAudioLevel);
         }
     }