Mute/Unmute audio and video
publisher.publishVideo() method you can toggle audio and video. For these methods to have effect your Publisher object must have been initialized with
audio: true and
video: true respectively (see Publish a stream section).
publisher.publishAudio(audioEnabled); // true to unmute the audio, false to mute it publisher.publishVideo(videoEnabled); // true to enable the video, false to disable it // (a black screen will show up instead)