*More info and testing on the card*
I verified and i do not have balance issue between Left and Right. It is perfectly even here. Also, there do not seem to be an utility for balance with the disks, there is one for volume only.
I also tried the card in a pentium 120 and the sound cuts. Its actually worse than on my celeron 500.
I then tried on my overdriven 486 and it works perfectly (evergreen 5x86 133 ) There definitely seems to be a glitch when this card runs on something more recent than a 486. The card was made in 1991 so that could make sense...
Also, this card can use Gameblaster CMS (SAA1099P) chips (not sure if usually included ) but i have them on my card. I tried Monkey island with these things and it seems to work all right! I do not have an actual gameblaster to compare but my guess is its pretty close.
Compatibility wise, this card so far is sort of average. here are the games i tried and the results.
Duke nukem 2 : FM music + digital sound is Good
Wolf3d: FM and digital sound is Good but adlib effects seem distorted because too loud ( it seems )
DooM: FM music is good, no audio.
Comanche Maximum overkill: nothing works
Descent : All good
OMF2097: All good
Dune: FM music is good, forgot to check audio
Monkey island : Adlib FM music is glitched, really not pleasant, its plain wrong. Howerver CMS was fine.
All this being said, there is something great about this card. The FM quality (when it works) is GREAT! Really its excellent. It has a real OPL2 and the amplification circuit must be pretty good because this thing has sound i tell you. Its clear and meaty at the same time.
I also tried to use the gameport for general midi output, during the installation you have the possibility to test midi out but that did not seem to work with my sound canvas module. Apparently , you cannot configure port settings anywhere for the midi out which is a bit strange. When tried in a game it says <mpu-401 port 330 not found > I did not bother trying other ports.
sprcorreia, do you happen to have the Manual for this thing? It could tell us how the midi out is supposed to work, that would be nice of you to check.
FM sound card comparison on a Grand Scale!!
The Grand OPL3 Comparison Run.