OPL3SA2_MIC
tmp = snd_opl3sa2_read(chip, OPL3SA2_MIC);
snd_opl3sa2_write(chip, OPL3SA2_MIC, 0x8a);
tmp1 = snd_opl3sa2_read(chip, OPL3SA2_MIC);
snd_opl3sa2_write(chip, OPL3SA2_MIC, 0x9f);