I have a D12 receiver in my living room hooked up to a SD television. For some reason, a lot of the channels seem to have "artifacts" associated with them and the picture quality is not that good. The Eagles-Giants game on NBC was really bad. Has anyone experienced this? I have the receiver hooked up to 2 tvs and the other one is fine. I've mess with the settings on the TV but to no avail. Any idea what causes this?