Any advice please. The VCR is old but hardly used and the manual is, of course, MIA. It was functioning beautifully until yesterday. Now, when we play a tape all we see are horizontal b/w lines on the screen and no audio whatsoever. However, when in MENU mode you can hear the audio perfectly but, of course, you see a blue MENU screen. Additionally, I noticed that upon tape insertion the letters "DT" illuminate on the LED and then blink and disappear after depressing the MENU button on the remote. I've tried all of the limited possibilities with no luck. Any ideas??