I've been using linux since around '99 and if I had a map of linux subsystems then audio would still fall right in 'Here be Dragons' territory for me. I knew enough to come up to the border and set up an outpost to get audio out but I dared not venture deeper.

To be fair besides getting audio out I never really needed to go deeper until I started an audio-heavy personal project a few weeks ago. This article certainly helped clarify quite a bit of the map.