The VCR is probably not it, and existing on two different decks eliminates those.
Remember, and ES10 is not a TBC. Perhaps it's interacting poorly with your tapes? Try to bypass it.
You do have a TBC, right?
Capture card possible.
Amarec is not as tried and tested as VirtualDub
, so I'd suspect it as well.
RAID-0 can cause issues with video, and I said that over 15 years ago. I saw issues as far back as 2001. However, less likely here, due to frame duping.
Windows 10 is a mongrel, but again unlikely here.
Time for process of elimination. ES10 is main suspect for the moment.