The Link, Dixons, Currys Digital are all the same company - DSG. They are notorious for taking used goods back from customers who've had problems, repackaging and selling as new. This wouldn't be quite so bad if they had staff who could actually properly check that the items really are exactly as they were originally sold and complete. I had a friend who took a broken CD player system back with a faulty speaker, the replacement also turned out to be faulty, the replacement for that was the original one she took back (she'd noted the serial number).

I would only buy from DSG if I inspected the item and made sure it was still sealed in the box... then I'd open it and check it was complete, undamaged, working etc.

Sorry if this is bad news.
Paul