I used to have the 43 E series and DV used to work fine with that. The P55-f1 however detects it, but cannot enable. I got it to enable once but it wigs out and resets the video etc.
Nine times out of ten with those symptoms, the issue is with the HDMI cable. Even if the same cable worked before, some TVs are more finicky about cables than others. Before anything else, I would get a new HDMI 18Gbps cable