setAudioTrack method

Description

Change the currently-loaded audio track (e.g. change the audio language, switch to an audio track describing what’s happening on the screen, switch to an audio track relying on more channels and so on.).

This methods takes a number in argument which corresponds to the corresponding track object’s id property. The main location where you may find those objects are through the getAudioTrackList method and the audioTrackListUpdate event.

You can also set the argument to null to let the WaspHlsPlayer set a default audio track.

setAudioTrack can only be called when the WaspHlsPlayer instance is in the "Loaded" state and thus when a content is currently loaded. Calling it in any other scenario leads to an error being thrown.

Influence on variants

Changing the audio track may also trigger an automatic “unlocking” of a variant previously locked through a lockVariant call, in which case you will receive the corresponding variantLockUpdate event.

This is because some audio tracks may only be compatible with some variants but not others. It should be noted however that such scenarios are rare and may only be seen in the few HLS contents which enforce such rules.

Note about its asynchronicity

As the WaspHlsPlayer relies on a Worker where most actions actually occur asynchronously, the audio track will not be updated synchronously after this call.

Likewise, calling the getCurrentAudioTrack method synchronously after calling setAudioTrack may not returns the characteristics of the set audio track yet.

You will receive a audioTrackUpdate event once the audio track is known to be actively loaded by the WaspHlsPlayer.

Syntax

player.setAudioTrack(trackId);

• arguments:

  1. trackId number|null: The wanted track’s id property (see getAudioTrackList method and audioTrackListUpdate event.

     Can be set to null to let the WaspHlsPlayer set a default one instead.