I searched and read the manual and nowhere does it mention drivers. This must have been a plug n play unit. So the next question has to be how are you connecting this to the computer?

More questions; how were you using this with BiaB and XP? Are those setups the same in your Win 7?

This unit came out in 1991 so you may have to run it in Win 95 compatibility mode. I am running an old but very useful photographic program from that era successfully in Win 95 compatibility mode.

As a last resort I would not run in duel OS mode. I would scrape the SC-55 and go to Soundfonts. There are free soundfont VSTis out there that are 32 bit so they will run in BiaB/RB natively. A good GM soundfont (there are plenty of free very good ones-just search for them) that may sound as good as or better than the SC-55. With soundfonts you can replace any single instrument with another and/or have a number of soundfont banks that you can load.

But for the best sound save up some money and buy a newer sound source.

BUT I still think that you can get your SC-55 to work. We just need to figure out what is going on!

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware