I sent my N900 off to a Nokia carepoint for repairs sometime in March for a malfunctioning USB port. I got it back a couple of weeks later, with nothing changed. I sent it off for a second time, and got it back exactly the same 1 month later. I contacted Nokia Belgium for this. I don't know how Nokia does it for the rest of the world, but in Belgium Nokia sends out a new device if repairs have failed 3 times in a short period of time. So hopefully I just have to wait a couple of weeks, and I'll either get my phone repaired or a new phone.