Obey AudioFocus Requests
Pauses or lowers the volume if another app requests audiofocus. Pausing or lowering volume is determined by what type of request the other app requests. Notification sounds typically will just lower the volume.
Stop On AudioFocus Loss
When another audio player starts playing, this will result in AudioFocus being lost. This setting will allow GMMP to ignore that loss and continue playback. This is useful if playback is desired while using another app that produces audio (like games).
AudioFocus Volume
Lower the volume to this value when another app requests a DUCK audiofocus request.