VF4's songs are built entirely out of loops (more like a MOD than normal sequencing)
Wha? That doesn't make any sense, since MODs are sequenced, plain and proper. Unless you're talking about those Amiga MODs that tried to get around the 4ch limit by sampling whole sections of the song... Though why Sega would want to do that on a 64ch chip is beyond me.
Also, latest dsfdtpk.py flagged all VF4 songs as SFX... Which means I need to go through all games once more, to check if it didn't do so with previous games too.