How to monitor who is speaking in the room with Express SDK?

• In the case of playing a single stream, after playing the stream successfully, call startSoundLevelMonitor and listen to the onRemoteSoundLevelUpdate callback to get the volume information.
• In the case of playing a mixed stream, first start the sound level option in the mixed stream configuration (i.e. enableSoundLevel set to "true"), and specify a unique "soundLevelID" for each input stream, then listen to the onMixerSoundLevelUpdate callback to get the volume information.