Oh dear. I feel your pain.
I got my files across in the end. The fastest way was ethernet port on the PC to ethernet port on the DNS-320 and leave it overnight three times, transferring smallish batches of files each time (40-50GB).
Now I only move one or two GB at a time and it's fine.
I've also installed Twonky and my Samsung TV sees all the files perfectly.
I'm very happy with my DNS-320 for now.
Yep annoying …..
I’m now chucking 500GB a time on to a USB drive and using the copy function so I can shut the pc down while the copying is going on. It sits there quite happy copying the drive.
Oh one tip when doing this
The copy function only copies to volume 1 and if you need the data on volume 2 it can be quite time consuming copy over from 1 to 2.
So to save time I just shut down the NAS and yank out volume 1 and turn the NAS back on. It auto relabelled Vol 2 to Vol 1 and copies the drive with no problem.
Then I shut down drop Vol 1 back in and job done. Oh as you now have 2--- Vol 1 drives the NAS auto rename it back to Vol 2..