I don't mind trying things on it. It's a VM after all, and we do have this wonderful snapshot feature. 
I did netsh interface tcp set global autotuning=disabled, then rebooted (just for good measure).
There was no change to the symptom. Probably says the bug/glitch isn't in the autotuning feature.
My own personal thoughts are that maybe somehow the change in the Windows scheduler so that interrupts don't occur at regular 1/1000 second intervals but are now variable has somehow affected a driver or protocol implementation.
-Noel