Thanks for confirming it works. I've got the older gray Action Replay 4-in-1, so no switch on top and no save compatibility after flashing Psuedo Saturn Kai to it, which I think means I don't have to do anything to it.Super Tempo works fine for me with the default CWX loader. If you're using one of those all-in-one cartridges then your first port of call is to add shielding in order to fix compatibility issues caused by electromagnetic interference: PPCenter :: Pseudo Saturn Kai Compatibility List
Going to assume a bad burn or bad rip, I'll do some testing with Nero DiscSpeed which seems to be working alright now, and burn another. My Saturn disc drive's laser was replaced with a new one from Aliexpress that seems to be working fine on all official discs.
EDIT: Retroarch on PC, loading off the same disc, locks up for a second at the same spot on the intro and then plays the music starting at the wrong spot, so just a bad burn
Maybe you can still get fancy Taiyo Yuden discs... (checked and you can btw)