i noticed that whenever i switched off and switched on again my phone, the phone is then automatically change to headset mode (eventhough there's no headset connected) thus i can't make or receive call without having a headset. One more thing, i noticed that the phone asked for wallet code whenever i try to access my wallet ( eventhough i key in the right code, set the codes before ).. i've search through the internet and some say it's a bug on 6510... does anyone have any solution for these problems? please help me....