dec 06 i purchased a mitus hd 73" tv. the cbs hd channel is 131 and it is accessed off an antenna. this channel was available last night but not today. today i get a message channel no longer available. i ran a systems check. no signal. all other channels are fine, nbc, fox and abc. i changed it to the secondary tuner no luck. the system does not recognize 131. i called the local staion- they are sending out a signal. i verified this info by checking 131 in my rv. it works. any ideas? please help!