I've noticed a peculiar issue that has only presented itself about 3-4 times since I received my phone last Friday. When in Silent mode, the phone appears to glitch up and vibrate while showing the Silent Alarm picture. As if I had just put it into silent mode even though I haven't touched anything but the screen. I haven't seen anyone report on this and I would like to replace the phone but I doubt I could prove this to the genius bar since it occurs so randomly. Any ideas?