Thank you for that link. It certainly seems related.
I just checked my Audio Streaming Settings and my only option is Windows MME, so I’m already running that. My audio is fed out of my NVIDIA GeForce GTX 680 video card’s HDMI output to an Onkyo PR-SC5509 receiver. Strangely, I never had this problem with my previous machine running through the same HDMI → AVR configuration.
Edit to add: I just tried using my Avid Fast Track Duo audio interface, which I generally don’t use due to it being stereo-only. I get the same behavior.