I would've liked to make the music during the jam (it's a skill I don't have, but I'd like it gain at least a rudimentary understanding), but I ended up having far less time in the second week than I anticipated. It was probably for the best when it came to the quality of the songs in the game, but it was a bit disappointing to me personally. You can see links to the creators on the game page.
Your comments on the volume are noted, and I'll keep that in mind for when I update the game after the rating period ends. The intro rule text is also top of mind for me, as various people have had similar concerns. Thanks for your feedback!