Yes i have the same issue, where sometimes the connection is flawless, then it still indicates it is connected but if i try to open say the playstore it times out, only to come back randomly, ill see if i can discover any patern in it.now IMEI still there after many reboots but , sometimes , signal is like frozen I see 3g icon and quite good reception but I cant call or go on the web , If If I try to call , I can't end the call , it stays in notification bar and call never end until I reboot the phone , dis someone notice that ?