I do not have any systems based off of this chipset, but there are a few methods you can try to get your sound working. First, over at the
Alsa Project, they have the Yamaha OPL3-SA2 listed
here with instructions on how to use it. I personally use premade Alsa RPMs from
Fresh RPMs. Also, the Alsa RPMs from Fresh RPMs comes with /usr/sbin/alsaconf (not 100% sure since I am away from my Linux machine at the moment) which should place the proper modules into /etc/modules.conf. If this doesn't work, I would recommend downloading and burning
Knoppix. It has a really good hardware detection script. You can then run /sbin/lsmod and see what modules are loaded. Or, you can go to
the Arch Linux hardware detection page which uses a modified Knoppix script. Good luck.
--SN