internal static extern int snd_mixer_selem_set_capture_volume(IntPtr elem, snd_mixer_selem_channel_id channel, long value);
public static unsafe extern int snd_mixer_selem_get_capture_volume(IntPtr elem, snd_mixer_selem_channel_id channel, long *value);
internal static unsafe extern int snd_mixer_selem_get_playback_volume(IntPtr elem, snd_mixer_selem_channel_id channel, long *value);
public static extern int snd_mixer_selem_set_playback_volume(IntPtr elem, snd_mixer_selem_channel_id channel, long value);