tab1:# hda-verb /dev/snd/hwC0D0 0x20 SET_COEF_INDEX 0x07 nid = 0x20, verb = 0x500, param = 0x7 value = 0x0 tab1:# hda-verb /dev/snd/hwC0D0 0x20 GET_PROC_COEF 0 nid = 0x20, verb = 0xc00, param = 0x0 value = 0x7ca0 I do not understand the second part of your instruction so I cannot complete it. But posted above are the results from the first set of instructions.