https://bugs.winehq.org/show_bug.cgi?id=41599
--- Comment #14 from Andrew Eikum aeikum@codeweavers.com --- (In reply to celestialtuba from comment #11)
(In reply to celestialtuba from comment #10)
I can confirm this is happening to me as well. This was happening to me on Ubuntu 14.04 using Wine 1.9.16, as well as on 4.8.8-2 Arch using 1.9.23. It started for me on the voice chat patch. It does seem to be coming from battle.net as others suggested, however in addition to whenever I receive a /w, it also happens when one of my "favorite" friends logs on or off. I'd be happy to provide anything I can to try to help fix this issue.
Now that I think of it, I think this coincided with installing pulseaudio. I remember I was relieved when I installed WoW on Arch that I wasn't getting the loud bursts of static anymore, and out of the blue it started happening again. I did not connect the dots in my head until I saw someone say something about pulseaudio, so I think this may be a pulseaudio specific thing.
Nothing to do with PulseAudio. Likely your ALSA setup was allowing only one application to play audio at a time, so the B.net client was unable to play its broken audio. Installing PA allowed multiple applications to play audio, and now you can hear the bug.