If you have an iPhone 4S and also have an iPhone 4 try this little experiment out for me. Wake your 4S device to the main screen and put it to your ear like you are making a call; listen very carefully. In the two new units I have tested it on you can here a noise, almost like the worlds smallest hard drive ticking. On my old iPhone 4 or 3Gs I hear no such noise. I know this isnt a small hard drive inside, but on the engineering side what do you think is making this noise? PS, I a not asking this because I think something is wrong, I just want to understand for geek reasons.