I've tried using a PCI soundcard in much the same setup (arcadeOS with AdvMame) but never got the thing to work. However I've heard of some PCI cards working without a problem.
Las Vegas has some Autoexec.bat settings for a few different PCI cards (Ensonic, SBlaster128, SBlasterLive, Via Onboard etc.) here:
http://members.cox.net/mame1/software.htmHe's got a great guide to getting ArcadeOS/AdvMame up and running.
In the end I just dumped the PCI card and replaced it with a cheap ISA SoundBlaster from EBay; which worked no problems.