VALID_AUDIO_IO_MUTE_LEVEL  530 include/sound/vx_core.h #define VALID_AUDIO_IO_MUTE_LEVEL		0x04
VALID_AUDIO_IO_MUTE_LEVEL  286 sound/pci/pcxhr/pcxhr_mixer.c #define VALID_AUDIO_IO_MUTE_LEVEL	0x000004