my iphone got no sound just happened suddently, when i pick up a call, there is no sound coming out from the telephoen receiver, i tot it was line problem, after trying few times and i get to know the iphone detect as i already plug in headset which actually i never plug in any headset, so it result no sound coming out from speaker or receiver, no matter i play music, apps or even call, please help me is it hardware problem or i gonna send it to maxis centre?? i had try restore to factory setting still the same problem occured. and i havent try to restore because itunes promt me to update to 3.1.3 which cannot be jailbreaked at this moment.