I have a update for Modem. It's for the L Version! (Modem.bin) from I8190LUBANE2 Firmware.
The File is taken from UFN I8190LUBANE2 Firmware (Argentinia / Movistar).
1.) Perform a Backup
2.) Install via CWM or TWRP Recovery
3.) Clear Cache & Dalvik Cache
4.) Reboot two times
As usual : I am not responcible, if something unusual happens or the Phone is not working after reboot !