I am having a problem where another channel 'overlays' or interupts the channel I am watching. There are two offending channels: 1495-ZLiving and 1483-Recipe.TV. This is what I see.
I am watching the network news and suddenly another station appears (Recipe.TV). I was not near the remote and nothing else was going on in the room. When I pressed Info on the remote, it indicated I was still on the CBS channel, but I'm seeing a recipe.
Another event. Changing the channel and as the new channel appears, ZLiving appears at the same time. I am actually watching both programs at the same time.
This has been happening about once a week. Lately, it is happening more frequently. I have only one TV and one DVR.
Bad news -- good news.
Apparently, no one knows (or admits to knowing) what causes this. Clearly it is the 'head end' of the Comcast network. It seems to happen on newly added channels.
The good news is that it seems to correct itself after several days. So, my problem went away after a week.