HI Jocko,
here is a file where I attached the output of the commands you suggested (disk are i and j right now).
If needed I can reformat the disks. Maybe it is advisable to scan for bad sectors?
The usb spin down guard is disabled.
I initially formatted the disks time ago, with a linux distribution, but I don't remember right now. I don't think I formatted them from the NAS, no.
Thanks.