During New Year's Eve, after standing out in the freezing cold, my friend finally let me in his apartment. I showed him my phone and to my surprise, the screen did not respond at all. It took about 5 mins before it responded at all. Pretty embarrassing for a $400 piece of equipment. At first, I thought it was the cold and because I had a plastic screen protector on it (the original protector that came with it, I just cut off the excess piece and in the top speaker). But today, it was even colder, about 0 degrees F and I was outside even longer but when I got into the hospital, I tried the phone, and it worked fine. So, how come it was unresponsive the first time when exposed to the cold but not the second time? Is it possible that the cold has nothing to do with it and I can expect more non-responsiveness from the screen inthe coming months? Should I just return this unit right away before the symptoms get worse? Thanks.