Do you know if there is anything else broadcasting out of that station? If there is and you get that other channel fine, then yea it's probably something to do with the tuner in your TV. In which case, you might try using an old VCR or a similar device if you have one, as it will have its own tuner.
If there isn't anything else coming from that station, then there might be something creating interference or blocking the signal between you and the tower. In which case, you might try re positioning your antenna, but there may not be much you can do.