So, instruments right now have a strange quirk. If you try to paste a song from the wiki, you'll find that most of the time, it'll be way slower or faster than the actual song was. you may notice that a song you pasted in with 180 BPM has been set to....171???
The instruments themselves are hard-locked to a set of preset BPM values, and you can see these when clicking the + and - buttons.
The preset ranges don't really....work with most songs, so a lot of the time, you end up with stuff that sounds off, like, annoyingly so.
Posted this on the github, but it was marked as a feature request instead of an issue, so uh, closed it and moved it here where it can be properly ignored. :)