I bought an ipod touch from best buy about a month ago, and I took it back since it had one visible dead pixel on it. They gave me a new one, and it worked fine for a couple weeks. Now, there's a newly developed dead pixel on the screen. Has anybody else had this problem? It's starting to irritate me, and I might just ask for a full refund this time around. Does the software update help fix any dead pixels? Thanks!