I have the exact same problem, except it affects my cheapo keyboard. Almost every time I move from my desk, the Num/Caps/Scroll Lock LEDs flash up as the controller restarts. And since it's a PS/2 model, if I'm holding a key and let it go as I'm standing up, it never sends the termination sequence and keeps typing it until I press it again.

I'll definitely try some of the tricks from this article.