I believe you've got a corrupted tystream. I've had the same thing happen to me on occasion. If the show will be on again just re-record it the next time around. I just bought a 2nd DTivo so I can do backup recordings simultaneously in case the main DTivo refcords a flaky tystream. I'm in the process of archiving several different series and there's no telling if the series will be repeated once it cycles through its current run.
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