I'm seeing some odd behaviour in Windows Media Center 7. It seems like all channels (apart from 1, 2 and 3) look like this:

http://www.flickr.com/photos/nih7777/3988165867/

The picture of the girl is static, with the colours of the feed still coming through and the saturation maxed out.

I haven't changed anything that I'm aware of. The only codec pack I have installed is the CCCP one, but that's been working fine for months. I have updated the nVidia drivers several times. I don't know if that caused it, but it didn't fix it.

Any ideas?