Ok, I am very obsessive compulsive when it comes to new electronics. I've just recently got an iPhone. I've noticed that when I have it on for more than five seconds or so and hit the lock button in the top right, the locking sound emitted by the iPhone is not totally in sync; when I click the button, the locking sound comes about 1- 2 seconds later. However, I've noticed when I quickly unlock the phone and re-lock it again the sound is simultanious to when I hit the button. Is this normal?