I recently installed this on my offline 'retro' XP machine. I get very low FPS (under 15fps) but only when voice tracks play. I have a smooth 60fps at all times otherwise. It is very odd.

I've tried different 3d sound settings in the menu options to no avail. I've tried changing AA/AF in case that had any effect. Same happens with the onboard VIA audio enabled and the Audigy disabled.

I'm using the D3D mode as I can't get 3DFX working on this machine.

Retro Specs:
Athlon 64 3200+
9600 Pro
1GB RAM
400GB SSD (get removed and TRIMed regularly in another PC)
SB Audigy 2 ZS
XP SP3
DX 9c

Any help is appreciated. Not encountered this problem before.

Further information. It works fine in WIndows 10 but obviously lacks EAX, etc as I don't have the hardware (creative sound card) nor the OpenAL software. The main reason for the retro machine is having all the bells and whistles from the time.

Maybe I'll just find the original CD and see how that works. I've probably still got it in storage.

You can try indirectsound.

https://www.indirectsound.com/downloads.html

As a workaround on W10?

I can see it does possitional audio but I can't see if it emulating EAX effects.

If you want EAX you can try this:

https://community.pcgamingwiki.com/files/file/28-creative-alchemy-universal/

You could also try the latest version of dgVoodoo 2:

http://dege.freeweb.hu/dgVoodoo2/dgVoodoo2/