How to deal with the sudden silent audio or black video due to tracks being stopped?

Problem

During a call or live broadcast, the audio that a web client is sending suddenly becomes silent, or the video goes black. After checking the log, you find that this occurred because the audio or video track stopped.

Reason

The most likely reasons why a track would stop are a loose or poor connection, or the device has been disconnected.

Solution

The applicable solution depends on the version of the Web SDK you are using.

Web SDK v3.x

The Web SDK v3.x does not support hot plugging. If you remove a device and reconnect it in, you must create a new stream. You can fix the issues of silent audio or black video due to stopped tracks as follows:

1. Listen for the stream.on("audioTrackEnded") and stream.on("videoTrackEnded") events.
2. When the SDK triggers the stream.on("audioTrackEnded") or stream.on("videoTrackEnded") event, use a popup window to remind the end user to check whether the device is working or to reconnect the device.
3. Call unpublish to stop publishing the audio or video stream.
4. Call createStream to recreate the audio or video stream object.

Web 4.x

The Web SDK v4.x supports hot plugging. You can fix the issues of silent audio or black video due to stopped tracks as follows:

1. Listen for the localTrack.on("track-ended") event.
2. When the SDK triggers the localTrack.on("track-ended") event, use a popup window to remind the end user to check whether the device is working or to reconnect the device.
3. Listen for the AgoraRTC.onMicrophoneChanged or AgoraRTC.onCameraChanged callback to get the device status. When the device is connected, call MicrophoneAudioTrack.setDevice or CameraVideoTrack.setDevice to use the device.

See also

• Hot plugging of audio and video input devices (Web v4.x).