I recently used PlayOnLinux (PoL) to install a supported game and found that it had no sound. Running wincfg via PoL showed that there was no audio driver installed.
I had searched everywhere online, checked the errors in the debug log and installed various audio-related packages that I thought might be needed, deleted everything from PoL and reinstalled the game, but still winecfg showed no audio driver.
However, when I created a new virtual drive and ran winecfg on that, it showed that an audio driver was installed and the sound test suceeded. I found that it was possible to export the registry key below from the test virtual drive, and import it into the registry for the game profile.
PoL shares the "My Documents" folder between game profiles, so saving the .reg file there made it easy to export and import quickly. I also had to delete the default driver that appeared in the game's registry.
(N.B. You can create a new virtual drive by selecting the installed game, clicking "configure" in the actions panel, and clicking the "new" button.)
Anyway, I'd searched high and low for a solution to the above and found nothing that worked for me, so I thought I'd post the above in case it helps anyone else. :-)