Hello, Please reboot your cable box- or whatever other source is connected to the HDMI port- that you are viewing. Shut the Pioneer receiver OFF, then pull the power cord from the wall plug to the cable/SAT box, etc. connected to the receiver.
While it's unplugged check that the HDMI cable is connected securely on both ends (the box and the Pioneer). Plug it back into power and give it a few minutes to reboot. Then turn the Pioneer on and see if you still have the same problem.
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