There's nothing wrong with your antenna, amplifier, or cabling. The problem is the TV set itself (which you didn't identify). Most likely, the problem is a corrupted channel scan map/memory. Also possible is a TV set firmware incompatibility with the data that is being transmitted by WTBS/WANN.
You may wish to proceed as follows:
1) Try a simple rescan.
2) Try a "Double rescan" as per
http://www.dtv.gov/rescan.html
3) Look a a master reset in your TV's menus, then rescan
4) Contact the tech support/ customer service department for the TV set manufacturer.
5) Contact the engineering department for WTBS/WANN and see if they have any insight.
Good luck and let us know if the problem gets resolved.