How do I trouble shoot the DVD recorder. It does not respond to the record button. I have tried using different blank DVDs. Am using DVD-R. The vcr records fine. the dubbing from dvd to vcr works fine but there is not recording on the DVD from vhs or tv or cable. Can you advise me as to me steps to achieve the cabability. I don't remember if I have ever tried to record on dvd before. thank you