GUSMASK_LOOP_ENABLE
sc->sc_voc[GUS_VOICE_LEFT].voccntl &= ~(GUSMASK_LOOP_ENABLE);
sc->sc_voc[GUS_VOICE_LEFT].voccntl |= GUSMASK_LOOP_ENABLE;
sc->sc_voc[GUS_VOICE_LEFT].voccntl &= ~GUSMASK_LOOP_ENABLE;
sc->sc_voc[GUS_VOICE_RIGHT].voccntl |= GUSMASK_LOOP_ENABLE;
sc->sc_voc[voice].voccntl &= ~GUSMASK_LOOP_ENABLE;
sc->sc_voc[voice].voccntl |= GUSMASK_LOOP_ENABLE;
sc->sc_voc[voice].voccntl &= ~GUSMASK_LOOP_ENABLE;
sc->sc_voc[GUS_VOICE_LEFT].voccntl |= GUSMASK_LOOP_ENABLE;
sc->sc_voc[GUS_VOICE_LEFT].voccntl &= ~GUSMASK_LOOP_ENABLE;