I recently bought an R9 380 from newegg, I got it last Monday. I use dual displays, one HDMI, one DVI.
Occasionally, the HDMI will play garbled, trashy audio. However, my headset will play audio fine.
At first I thought it was an audio only issue, however, I've since realized that it actually -slows- video playback as well.
If I set my default audio device to my headset, then video playback is fine, normal speed, and audio is fine as well.
However, setting it to HDMI causes the video to slow.
Rebooting my computer fixes this issue temporarily.
I've been reading around and seeing a lot of complaints about AMD's crimson drivers, so I tried uninstalling the Audio drivers (no success)
As well as reinstalling the drivers entirely. (No success.)
I didn't have this trouble on my old card (GT 720)
I'm trying to figure out if it's a driver issue, or if I should just RMA the card, however I have until the 31st of January to figure that out.