Sound either is not there on start of game or goes out right after starting to play. It works for a little bit some times then goes mute. It has been completely random.
I also have been having this issue. Another detail worth noting is that my headphones still work for other items on my PC. To be specific, when the sound cuts while plauing D4, I switch to another application that uses sound and my headphones are working, but switching back to D4 shows they do not work on D$. If I restart headphones while in D4, they work again, but soon cut-out again.
Definitely something related to D4.
Yes, I checked, all my drivers are up to date.