Advanced features

Learn how to control audio for each user with granular audio control, share a second microphone, and play an audio media file.

Granular audio control

In a single session, you can control the audio that each user hears with the muteUserAudioLocally(userId) function. This does not mute a user's microphone. Instead, it stops the SDK from playing a certain user's audio to the user this function is called for. For example, you can use this function to build a backstage experience. Or in a fitness class so that each user can hear the instructor, but not the other users taking the class.

In a similar manner, you can control the volume level you are hearing from other users with the adjustUserAudioVolumeLocally(userId, volume) function.

Share second microphone audio

You can share audio from a second device, such as a stethoscope using the startSecondaryAudio function. This feature is available using the following platforms and browsers:

  • Chrome, Edge, and Firefox on Windows
  • Android browsers with audio compatible mode set to true

Safari and macOS not yet supported.

Once the user grants audio permission, get the list of microphones with getMicList and pass a deviceId into stream.startSecondaryAudio.

let microphones = stream.getMicList();
stream.startSecondaryAudio(microphones[1].deviceId);

Use stream.stopSecondaryAudio to stop capturing audio from the second microphone.

Play audio media file

You can use a media file to play audio in a session. Pass in the audio url as an object in the mediaFile property of the startAudio function.

await mediaStream.startAudio({
    mediaFile: { url: "https://example.com/audio.mp3" },
});

Note: If you want to use a video file (mp4) as both the video and the audio input, make sure the URL is the same for both the startVideo and startAudio functions. Be sure that the media file is from the same origin or has the necessary CORS headers for cross-origin access.

Use switchMicrophone to switch between a media file and a microphone device.

await mediaStream.switchMicrophone({ url: "https://example.com/audio.mp3" });

To control media file playback, use getAudioMediaPlaybackController to obtain a controller. This allows you to use methods such as play and pause to control playback. You can also set the playback property to control whether the media file's sound is played locally.

const controller = mediaStream.getAudioMediaPlaybackController();
// pause
controller.pause();
//play
controller.play();
// playback the sound
controller.playback = true;

See Play video media file for instructions on how to use a media file to play video in a session.