Casio Collectors

Any thoughts on what might be a causing a SK 5 to sound bent even when all the bends are removed.

My casio has a patch bay (and a bunch of other bends - pitch control, Slow AD, Phat Filter mod).

After opening it up, and doing basically nothing, it went all weird. Like it was automatically bent. Grounding Pin 25 of the ROM chip makes it less weird, but still weird.

Checking the video:

Thanks in advance.
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