I've just sold my ICY BOX IB-4220-B on ebay and have had a request for return as the buyer is saying although this says gigabit dual raid nas he's only getting 150mbps on testing, nowhere near the 1000mbps a gigabit NAS is supposed to offer. any idea why or what could be causing it or how I could test it when I get it back. I've had virtually no experience with NAS and this was only setup for a shortwhile before I reboxed it.