mixer_set_input_port
mixer_set_input_port(mixer->amixers[amix*CHN_NUM], rsc);
mixer_set_input_port(mixer->amixers[amix*CHN_NUM], rsc);
mixer_set_input_port(mixer->amixers[amix*CHN_NUM+1], rsc);
mixer_set_input_port(mixer->amixers[amix*CHN_NUM+1], rsc);