Swap the sets and see if the trouble follows the set. If it does you have a reason to complain to the maker.
I have a panasonic tcl32c12 television. We began using an antenna instead of cable a year ago. I can only get about half of the channels that I am capable of getting. The channels i can't get say "program not available (1)" I know it is a problem with the tv and not the antenna because I don't have the same problem on the TV downstairs. All was working fine until today.

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