ESSSB_IREG_MPU401CONTROL 1550 sound/pci/es1938.c 		snd_es1938_mixer_bits(chip, ESSSB_IREG_MPU401CONTROL, 0x40, 0);
ESSSB_IREG_MPU401CONTROL 1837 sound/pci/es1938.c 		snd_es1938_mixer_bits(chip, ESSSB_IREG_MPU401CONTROL, 0x40, 0x40);