I tried everything I can with return to zork and it isn't taking WSS. I figured out that the DMA for sound blaster and WSS have to be the same or sound blaster settings won't work. I have tried different IRQs but that doesn't seem to help.
One thing I noticed is that Descent specified WSS by port number and DMA, while return to zork uses port number and IRQ. Return to zork also includes its own wss driver that it calls and loads high in a batch file. Maybe the driver is incompatible? It's sndsys.com.
I took at look at the RTZ.CFG file in a hex editor and I tried to force a DMA through there using my best guess as to where it would go. That didn't work either. Maybe it never worked in the first place. I have no idea. I don't know how much it matters, because I suspect that the voiced bits are actually streamed from redbook audio because they sound pretty clean and the disc has a lot of audio tracks and uses midi for all the music....but if they were digital PCM samples, then 16 bit audio would really help it out a lot.