The problem you are experiencing may be that some older Set-top boxes (Cable TV or Satellite TV boxes) do not recognize an HDMI Repeater device connected between itself and the Video Monitor. This is due to the Set-top box being older and the firmware was not written to understand any type of Repeater (switching) device such as the Yamaha receiver. Because of this, your setup will not work properly with your current Set-top box. In order to fully incorporate the Yamaha receiver (or any other HDMI switching receiver) into your home theater, your Set-top box will need to be either replaced with a newer model or have a firmware upgrade installed. In order to resolve the issue with your set-top box, please contact the cable/satellite Customer Service Dept. and ask them to include "HDMI Repeater Support" in their boxes.
Be assured that the Yamaha receiver is fully HDCP compliant as well as HDMI compliant so it can pass any HDMI signals that are encoded with an HDCP flag.
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