Maybe a HDMI pairing issue? How are things hooked up? HDMI -> receiver -> tv? Need more info here.
Best way to narrow where the problem is will be to find out what item has the problem as it's unlikely they all took a dump. If you use the receiver for video passthrough then try hooking directly to the TV to see if it happens then.
Assuming you use HDMI:
It sounds like the HDMI out on the receiver and the TV input aren't syncing well. This could be due to a few things including a loose cable, damaged cable, or a failing port. Try reseating the cable, replacing the cable, or changing to a different TV input.
This is about as much help as I can be via the internet, good luck.