Hi, I need help for my iPhone4. Something is wrong with the ringer. There is no sound when I play the song, video and even games. When I click the volume button at the side, although it still pop up the ringer, the volume bar cannot be seen. But I can still answer phone calls and SMS. There is still ringing tone when someone call me. I try using headphone, the ringer works as normal. I have tried switching off the phone and re-on. It still did not work. Thank you!