Thank you for the update! Hmm. The sort-of-good news is that I believe this should be fixed in the next release, but that's obviously no good right now.
Could you try turning off your anti-virus (if any) and as much other software that might be running as possible? In particular anything to do with video capture could interfere.
Also, maybe worth a try: running in windowed mode? At least it could be an interesting data point.
Also: does having sound on/off make any difference?
Messing with 3D settings in the Nvidia control panel is also worth a shot, though I'm not actually sure which settings might factor in here. If it was an intel card, I'd suggest adjusting the "hardware acceleration level" slider (the one that goes from, roughly, "safest" to "highest performance" or something similar), but I don't think that Nvidia has an equivalent one, though there are a lot of other settings.