2112ci

Hi There I have a panasonic th-58pz850u, I have purchased a Denon Avr about 3 years ago, a 2112ci. Just recently the GUI from the Denon will not display on the Panasonic TV via the HDMI cable. I have tried all the HDMI on the TV and they all seem to work with the ROKU, BluRay and Directv box. I...