localMicrophoneAudioLevel
This returns the local microphone volume level. The audio volume is a linear value between 0 (no sound) and 1 (maximum volume). This is not a raw output - it is a smoothed-out volume level that gradually goes to the highest measured level and will then gradually over 250ms return back to 0 or next measured value. This value can be used directly in your UI for displaying a volume/speaking indicator for the local participant. Note: Doesn't return any values until the session is established!