Thanks for posting the job export - I think I may have misunderstood the error. This particular “hash mismatch” error only seems to come from one place in the code - when getting files from the destination and saving them locally as a temp file. (Assuming I’m reading things correctly.)
So I think what’s being reported is that a dlist file (a list of what’s been stored in a specific dblock file in the destination) has been downloaded into the temp folder but the resulting hash validation of the downloaded file doesn’t match what the local database was expecting so Duplicati treats the file contents as suspect.
My guess is that in the logs just before the hash error you’ll see a message similar to “Downloaded xxx MB in yyy seconds, zzz MB/s” (it might also start with “Downloaded and decrypted…”). If so, then it looks like the file being downloaded is the right size (otherwise you’d be seeing a different error) but the resulting hash of the file doesn’t match for some reason.
Assuming all of that is correct, it might be time to pull @kenkendk or somebody more familiar with the hashing checks into the conversation…
Just out of curiosity, do things work as expected if you enable the --no-backend-verification parameter? (Note that this isn’t a fix so much as a check for narrowing down when/where the error is happening.)