Well, re-install didn't fix it, but the good news is that I've discovered a few things.
Firstly, this is only a problem with HTML5, which I had been working with before, and on windows the music plays perfectly. Secondly, even though music pretty consistently hasn't worked on HTML5, short sound effects do. I realized this probably has something to do with the fact that the sound effect was uncompressed and then changed the compression settings on the music file. I found that the only setting where it didn't play at all was "Compressed - Streamed" which it had been set to before. The fact that it was set to that in the first place may have been a mistake on my part considering I'm not entirely sure what exactly this does. Since then, the music has started working, but most of the time it needs the sound effect to play first, which is still a bit of a problem but right now I'm just glad it's playing.
I have no idea what all this means or what to do with this information but hopefully someone does.