SNDCTL_DSP_SYNCGROUP
if (ioctl(config_in.fd, SNDCTL_DSP_SYNCGROUP, &sync_group) < 0)
if (ioctl(config_out.fd, SNDCTL_DSP_SYNCGROUP, &sync_group) < 0)
case SNDCTL_DSP_SYNCGROUP:
case SNDCTL_DSP_SYNCGROUP: