Windows 7 - WMC TV will play audio but no video

Hi all,

I've got a tv tuner set up with windows media center tuned to both digital and analog signals. It has worked great for a couple of months, but now all of the sudden it will only play audio...no video. It seems a bit inconsistent, sometimes the video will work and sometimes it won't. I think I have narrowed it down to something to do with the digital channels, because those channels are never showing video anymore, and when I try to switch to a digital channel and then switch back to analog, or even a recorded show, the video won't work on those channels as well.

Any thoughts as to what might be going on?