The ValueEvent object reports microphone gain or volume for microphoneActivityLevel and
microphoneGainChanged events. Both of these events are dispatched by Publisher objects.
The ValueEvent object defines the properties of the event object that is dispatched.
The ValueEvent object has the following properties:
target (Object) — The Session object that dispatched the event.
type (String) — The type of event ("microphoneLevelChanged").
value (Object) — The value related to the event.
For a microphoneActivityLevel event, this property is a number from -1 to 100. A value of 0 indicates
silence, and 100 indicated full volume. A value of -1 indicates an inactive microphone.
For a microphoneGainChanged event, this property is a number from 0 (muted) to 100 (full gain).