V6 Windows 7 Coherence mode jumps to full screen

I just installed Paralles 6 on a new Macbook Pro 13" and installed windows 7 32bit. I have multiple monitors setup and everything works fine with Coherence mode, but every so often Windows 7 pops out of coherence mode into full screen mode. I have changed all the power settings, sleep setting, and hibernate settings in windows 7 to Never but it still happens.

Any suggestions?

Thanks,

MIke