Sound.fadeOut(duration) will fade the Sound to a volume of zero over the duration given. At the end of the fade the Sound will be stopped and Sound.onFadeComplete dispatched.

Sound.fadeIn(duration, loop) will start the Sound playing, or restart it if already playing, set its volume to zero and then increase the volume over the duration given until it reaches 1. At the end of the fade the Sound.onFadeComplete event is dispatched.
Added AudioSprite to the build files.
docgen updates.
Removed the customBounds layer.