My iphone whilst in standyby/lock is not allowing me to receive calls. It does not ring nor vibrate. But when i press the home button, it shows a missed call and puts the time of the missed call at the point I pressed the home button. Calls can be received as normal when the phone is not locked but this is not ideal. I have reset, rebooted, upgraded and restored. Still occurs. Does anyone know of this problem and do you have a fix or any advice? It only started 2 days ago the phone is 2G and only 2 months old in excellent condition. Thanks for looking.