AUDIO__GAIN
audio__setgain((F), (V), AUDIO__PLAY|AUDIO__GAIN)
audio__setgain((F), (V), AUDIO__RECORD|AUDIO__GAIN)
audio__setgain((F), (V), AUDIO__SET|AUDIO__PLAY|AUDIO__GAIN)
audio__setgain((F), (V), AUDIO__SET|AUDIO__RECORD|AUDIO__GAIN)
case AUDIO__GAIN: