MV1B Cabinet - sound issues

[comatsu]

I recently purchased a fully working jamma wired cabinet with an mv1b pcb and a 138 in 1 multicart (seen before purchase and everything worked fine).

Once it was delivered I found that most of the games were playing without any sound.  A minority of the games play correctly with full sound, and I even found a couple where the sound effect work fine, but there is not background music.
Since sound works fine in some games, I am assuming that it is not a problem with wires/connections/speakers etc.
I have tried reseating the cart various times, but nothing changes.

Particularly none of the Metal Slug games on the cart have any sound, and I noticed that a couple of times before starting an metal slug game I get a rom check error (though this does not always happen).  Also happening with just the metal slug games, when I try to play them without sound the game often freezes after a few seconds of gameplay.

I am totally new to arcade cabinets so not sure what the issue could be, and if anything can be done to fix it, so if anyone can help me troubleshoot the issue I would really appreciate it.