* Figure out how to manage get_volume and set_volume
  * Should it be global? Does (audio_info_t)info.play.gain
    refer to the global mixer or just the track (i'm guessing
    from the manpage that it's global?)
* Find out if/how audio(4) supports 24-bit linear PCM
  * Audacious supports two methods-- one is 3-byte, the other
    is padded 4-byte. I'm guessing audio(4) doesn't support
    both, but who knows
* Clean up the code in terms of formatting/layout