Are you sure it's not the front disc brakes? Try holding the front brakes slightly and see if the squeak goes away. Mine do it all the time. A little bit of dirt will get between the pad and disc.
If not I would take it back if it's still under warranty or you could take it apart to make sure theres grease in there. It's not hard, take the wheel off and the main castle nut and your in.
If not I would take it back if it's still under warranty or you could take it apart to make sure theres grease in there. It's not hard, take the wheel off and the main castle nut and your in.