lower channels not coming in
I have a two-year-old Sharp 18" color tv. Three months ago, channels 2-15 stopped coming in at all, previously they did. Got new cable box & remote from cable company, who fiddled around wIth their signals (remotely) and still nothing comes in on those channels. My husband thinks it is a problem with the tv itself, but I am wondering why that would be. The upper channels all work fine (the ones in the basic service we are supposed to receive). The lower channels are all the local NBC, CBS, PBS, etc. feeds.
Any suggestions/help welcome!