I brought a iPhone 4S yesterday and I notice that I don't hear any sound such as alert sounds, keyboard clicks or lock sounds even though they are all turned on in the sound settings. The only sound that does work is the ring tone. Youtube has no sound either. If I make a call and then put it on speaker then bizarrely all sounds work but only during the phone call, when I end the call all the sounds stop working. If I press the volume up and down buttons on the side "Ringer" comes up but with no bar below it to say what volume it is at currently. If I plug headphones in I can hear all the sounds perfectly fine through the headphones. I've tried restoring the phone and setting it up as a new iPhone but that hasn't worked Genius Bar appointment I think!