While color correcting with CS6, my scopes stop working. If I shut down the program, it some times clears the problem. Other times, I need to reboot my system. It is a very frustrating problems.
Scopes are pretty intense in the graphics dislpay arena, so I would rule out an obsolete video driver first. Check with the nVidia, or ATI/AMD Web site, to see if there is a later version. Do not trust your OS, or any utility to tell you - check it out on the site.
That will rule out one possibility, and if not the "fix," then everyone can get about looking into other possibilities.