Panasonic AG-5710 sudden signal loss?
 

So I did a quick search and found someone who had a similar issue that was never resolved.
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Similar scenario, I've captured a few tapes using the AG-5710 over the last few days. Today when I went to do a capture, I get nothing but snow with audio, and the unit is indicating that it is an SVHS tape when it is not. I tried a tape that I successfully captured earlier in the week and same issue. Oddly enough, I had replaced another Panasonic deck (MD835 I think?) last year with the 5710 because it showed the same symptoms of snow with audio.

Does anyone have any ideas? The SVHS indicator coming on seems weird to me.

99% likely bad capacitors. Search the forum for AG 1980 and bad caps, these models are known for their capacitors dying and causing major problems.