The hardware is present, because the FM synth is built into the sound chip. ESS chips are more or less fully integrated and don't rely on too much on external hardware. Wavetable being an exception.

The ESFM synthesizer supersedes OPL3 so any game that has programming for that should be able to use it.

I do understand that the ESSFM supersedes the OPL3 - but I quite simply can't get anything to output sound on an OPL3 setting so far.

Nothing crashes or anything, there's just no sound.

Have you tried the drivers on this site? http://www.vogonsdrivers.com/index.php?catid= … menustate=45,35

I believe that computer is new enough to have a plug n play BIOS, which should make it easy.

Also, have you tried running your games in Windows?

If it's not complaining about the FM being missing then maybe the mixer setting is just set to zero for some reason. Try setting everthing to maximum with ESSVOL or whatever it's called.

Well, the short answer is that setting all of the volumes in ESSVOL seems to have gotten it functioning.

The long answer:
I decided to go to a clean DOS 6.22 install to reduce the number of variables to deal with. At first, still no dice, volumes on what I thought were the relevant channels (Master Volume, Synthesizer esp.) were set to 8, which is half volume. Still no luck.

I went ahead and set everything to 15 (Max Volume) which of course made things very noisy as the mic and line inputs were now enabled. That said, now the synth worked. I then turned the Master Volume down as well as the volume on the mic and line inputs, and the synth continued to work.

Not sure if it's an oddity of the implementation in this Compaq or if it's perhaps a bug in ESSVOL, but it seems to be sorted. Now to put 98SE back on there and make this back into the general purpose 90's gaming machine I was planning it to be - and hopefully still have the synth sorted.

Well, the saga continues.

Reinstalled Windows 98SE and the synth stopped working.

Attempted the same fix once I was in MSDOS mode - set all of the volumes to max in ESSVOL. No luck. I can't seem to get the synth to work.

I read somewhere that it could be the WDM drivers in WIndows somehow impacting it - I swapped over to the VXD drivers from Vogonsdrivers, still no luck although the Windows control panel now lists the Synthesizer as a controllable option.

Any other suggestions?

Anyone else have a similar issue with an AudioDrive and WIndows 98SE's DOS mode?

... And then I messed around with some BIOS configurations, reset to defaults and then maxed the synth volume and it worked again.

Really wish it was consistent.

I've also had trouble with some SFF Compaq desktops + onboard ESS but did not get around to mess with the mixer.
It seems it's not a hardware defect, we need to dig a bit more on this...

Since the ESS 1869 is Plug&Play, have you checked if perhaps Windows 98SE simply changes the i/o address of the FM port, which would explain it no longer working..?

That's quite possible - the synth was working pretty well after my last post. I've put the machine aside for a short time to work on another project, I'll post when I pull it out next.