AC97_ALC650_MULTI_CHAN_CTRL
ac97_reg_cached_write(dev, AC97_ALC650_MULTI_CHAN_CTRL, 0x0007);
ac97_reg_cached_write(dev, AC97_ALC650_MULTI_CHAN_CTRL, 0x8000);
ac97_reg_cached_write(dev, AC97_ALC650_MULTI_CHAN_CTRL, 0x8000);