I get a similar problem, though I just plug the PS2 and Gamecube directly into the AV sockets. I think the AV connections in the TV itself get worn or dicky. It happens with both my Gamecube and my PS2, so the problem might be your VCR's AV inputs. Also, what happens with me is that I either get a picture and no sound, or the screen goes to the standard AV screen. I just jiggle the connections, or unplug and replug until I am satisfied.
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