My converter box has worked fine with my vcr (yes, I'm old), but now when I put it on to record something, I get a lot of crazy lines all over the TV screen and can't get the menu to rescan or record, or anything else. It was fine before, but now the vcr can play tapes I have and not record anything new. The TV is fine, too. I have a rooftop antenna only. No changes were made before this problem began. Help!