The same thing happened to my phone. My advice is, take it to the shop where you purchased it with your reciept. Actually you don't need the reciept they will scan the phone. They sent it away for repair after stating "there is never any problem with these phones" (yea right) I didn't get it back for about a week, but it's fixed now and works better than ever
Hope this helps:D
Nikki, August 2007