Sorry for the slow response, I don't check this thread very often. It is, as you point out, fairly inactive.

Is the music also too slow? It could be there's a mismatch between the music's sample rate and the playback sample rate. Odd, but fixable.

The "now approaching" palette issue affects everyone, iirc it's difficult to fix. But it's on the list. I have a lot less free time these days, so it's hard to find time to work on OpenJazz. I don't know when the next update will be, though a fix for the music bug would certainly warrant one.