@dags:
Any success on this one? At first I suspected that the problem might the NIC speed of the DNS-343 could be set to a specific speed/duplex; but after looking at the specs on the DGS-1005D switch I see it's Gigabit as well.
Have you tried turning off the DNS-343, releasing the IP Address from DHCP, moving it over to the new location, and powering it back on?
Cheers,