Sorry to bring up an annoying topic...but I may have found something that helps. (I won't call it a cure yet...BTW I had enabled my stereo mix earlier that didn't work either)
However, one intriguing suggestion that just doesn't make any sense is to make sure you have something plugged into the analog MIC jack on the rear of your PC. I thought I did, but it was actually an extension cable, as I'm now using a USB mic. So I found an old pair of sony headphones (earbuds would probably work) And plugged them in. Thus far I've played for 2 days, and only had one fail and that was during a map change. This has something to do with Realtek audio and the way the game controls that port. Bear in mind, I have also put in all the other fix suggestions as well, so maybe it's a combination, but until I plugged in, none of the others had an effect.
FYI.... (and thanks so much for the assistance)
CRIMSON