Well I went to Futureshop and found my speakers on two displays. I put an ear against them to test and heard the same hiss. I tried other speakers and couldn't hear it (I only tried a few though). Seems it's confined to this particular model.
It's this model for anyone interested:http://www.futureshop.ca/catalog/proddetail.asp?logon=&langid=EN&sku_id=0770HDS0010124780&catid=19701
I would return them, but it doesn't really bother me. I don't sit 1-2 feet away from them so I can't hear it at all.