PLAYBACK_MUTE
case PLAYBACK_MUTE: return KEY_MUTE;
static const u8 autorelease = RECORD_MUTE | PLAYBACK_MUTE;
snd_ca0106_ptr_write(chip, PLAYBACK_MUTE, 0, 0x00fc0000);
snd_ca0106_ptr_write(emu, PLAYBACK_MUTE, 0x0, 0x0); /* Unmute output */