void unregister_sound_dsp(int unit) { sound_remove_unit(&chains[3], unit); }
void unregister_sound_midi(int unit) { sound_remove_unit(&chains[2], unit); }
void unregister_sound_mixer(int unit) { sound_remove_unit(&chains[0], unit); }
void unregister_sound_special(int unit) { sound_remove_unit(&chains[unit % SOUND_STEP], unit); }
void unregister_sound_synth(int unit) { return sound_remove_unit(&chains[9], unit); }
void unregister_sound_special(int unit) { sound_remove_unit(&chains[unit&15], unit); }