So you are saying zophar also used the wrong player? as the mp3s downloadable from zophar has the same issue.
I am using XMPlay and I tried the plugins:
in_gbs v0.4.2 and the song is way too fast, but still has the buggy bass notes
in_nez v0.9.4.8 + 3 + 24.10 song plays right speed but has the buggy bass notes
GME (rev .41fork) song plays right speed but has the buggy bass notes
maybe the game has a slightly different interpretation of how the music should be and therefore standard gb music driver doesn't play back the music right?