AC97_MIC_VOLUME_REGISTER
v = SHADOW(ac, AC97_MIC_VOLUME_REGISTER);
ac_wr(ac, AC97_MIC_VOLUME_REGISTER, v);
(ac_probe_reg(ac, AC97_MIC_VOLUME_REGISTER))) {
ac_mono_set(ctrl, value, AC97_MIC_VOLUME_REGISTER, 0);
ac_clr(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);
ac_set(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);
ac_set(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);
ac_set(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);
ac_clr(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);
ac_set(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);
ac_set(ac, AC97_MIC_VOLUME_REGISTER, MICVR_20dB_BOOST);