Panasonic Plasma Tuner Problem

[toughshift]

Connected to Apartment Building Community Antenna. Historically, works well. I have three flat panel sets connected to it. Two of them are working OK. However, the Panasonic 50" won't receive all the channels available. It was working OK for several years. So I did a re-scan. Now it receives even fewer channels. I eliminated possible cable problems by hooking up another good set to the same jack as the bad TV. I eliminated splitter problems by connecting the bad TV directly to the wall jack with a new cable. So, apparently something has changed (tuner?) in the TV itself. Any suggestions would be appreciated. Thank you.