Hi everyone, I used SAM unlock to activate my iPhone 4 GSM, and everything works well except that during phone calls the other party can't hear me, but I can perfectly hear them! It is NOT a hardware issue as some have suggested since I already had my iPhone checked at a repair shop and everything is fine with the hardware, so it must be due to the unlock not working properly. Does anybody have an idea on how to fix this? If not, how can I revert to Gevey, now that I've used the SAM method? Thanks for your help.