How many TVs? Can you try the receiver on a different TV?
Is the receiver hardwired (Ethernet or coax) or is this a wireless receiver?
As TV providers (broadcasters) provide either a 720p or 1080i signal.
This is what component cable is designed for, I would use component instead of HDMI cable.
HDMI is for 1080p, sometimes referred as BluRay, if using a streaming device from a streaming source sending in 1080p you would want HDMI cable. But this cable is from your game system, roku, etc type of device not the Uverse receiver.
Edit... Only use one cable or the other...
Do not have both a componet and a HDMI cable plugged into the receiver at the same time.
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