Use the advanced exchange and you never even have to see anyone and they send one first, it should go through sprint not asurion since it's happening from normal useage, but I would add in that it has been doing random resets just to keep it replaced through sprint in case they try to claim you abused it, and route you to asurion.
Select the "Self Service Phone Replacement Page" in the second paragraph
http://www.nextel.com/en/services/se...olutions.shtml