Looks like the upgrade was done by the same person who upgraded my Sony 700P to MSX2+ (it was upgraded before I bought it although) !!!
@Repair-Bas:
It sure wasn't you Bas ! I recall you ripped it out and replaced it (with a properly done upgrade) as soon as you saw the wire-spaghetti
It is possible.
I have here lots of pictures of those MSX-computers destroyed by MSX-criminals
Bas upgraded my Music Module back then and it's a nice print with 3 chips of which 2 are DRAMs... and it connected on the original RAM position using a bunch of stacked sockets to raise it high enough... So it wasn't Bas indeed...
The pic Meits made of his upgrade is the same one Bas did with mine as well.
Can you please check what is the third chip (not DRAM) on your upgrade? I'm sure it handles the DT0/DM0 weirdness of the MSX-Audio, but I need to know what chip they used for this.
the small one is a
TI005 CS
LS125A