Thanks for the suggestions guys. I did try zip tying the HDMI cable to a set of component cables but in Panasonic's infinite wisdom the HDMI ports and the other connections are some distance apart and it still worked loose. It worked loose less often, but it still lost signal. And yes, the ports on the Panasonic are vertically orientated!

Hopefully, removing the cable's weight off the connection will solve this problem. I think I'll look for a screw or other connection point above the HDMI ports and create a support for the cable.

When all else fails there is always duct tape! LOL