I had CM10.1 on my G300 but was experiencing a lot of 3G issues (loss of signal or reboots when switching from Wifi to Mobile data) ; the phone was originally bought in Thailand, updated OTA from GB to ICS by one of the shop clerks, and until a few days ago, IMEI SV was 38. I decided to try out the latest ICS stock (see here ) in B952 to see if it would improve things. I flashed it and everything seemed fine (IMEI SV now 50), so did a full clean install of CM10.1 R2 (wipe & format data/cache/system, flash ROM, flash gapps).
The installation went smoothly and all my apps are working, except now the phone won't even connect to my provider's 3G network. I have to run it with "2G data only" checked. If I uncheck it, it immediately loses signal, and I get a "No service" notification. Check 2G again, and it registers immediately, accessing data with EDGE and GPRS.
Logcat shows things like this :
I/Use2GOnlyCheckBoxPreference( 739): set preferred network type=0
I/Use2GOnlyCheckBoxPreference( 739): set preferred network type done
I/UpdateCheckReceiver( 7904): Got connectivity change, has connection: false
E/MobileDataStateTracker( 490): default: unknown network type: 0
D/ConnectivityService( 490): ConnectivityChange for mobile: DISCONNECTED/DISCONNECTED
D/ConnectivityService( 490): Attempting to switch to WIFI
D/ConnectivityService( 490): Attempting to switch to BLUETOOTH_TETHER
D/NetUtils( 490): android_net_utils_resetConnections in env=0x4e620b90 clazz=0xf0500001 iface=rmnet0 mask=0x3
D/ConnectivityService( 490): resetConnections(rmnet0, 3)
I restored my CWM backup from before the Stock flash, and I now get the same thing, so it seems the B952 flash somehow broke the phone's ability to connect to 3G (it was flashed using POWER + VOL UP + VOL DN and update.app). Does anybody have suggestions as to what I can try to restore 3G ? I was thinking of reflashing the bootloader or RIL, but don't want to do any more damage if I can avoid it.