Not really clear if it's a Sony or a Sharp you have. Anyway, all you can do is try another camcorder and if that fails also declare the video and the audio as "gone" and "lost". Those things happen.
Kees
I have a VL-AH151U Sony Camcorder. We transfer video on Hi-8 tapes onto DVD for friends. Some tapes play back fine and some tape; which the owner swears there is footage on; is snow throughout with no audio. We take the tape out and play another tape and everything works again. What can we do?

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