Does it do so on all tapes? It sounds like you are experiencing a tracking or tape path problem. You might try taking the top cover off, then cleaning the video head. Info is available on the 'net on how to do this. If problem remains, play a tape and see it is wandering up/down across video head. See if any of the tape guides are broken or bent, causing tape wandering. you may also have a problem in the electronics, perhaps in the servo circuitry, which has to do with careful control of tape speed, video head rotational speed, and certain other parameters. If electronics are bad, then VCR is likely a tosser, unless it is a high $ rig. Most electronics are disposable these days, unfortunately.
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