well i know there are post on the quality of the calls on this phone ( mainly the other party struggling to hear what you say) . i have finally blown my top ! since i first got this phone back in May, this has been an on and off problem. today i made 4 calls this morning 3 of which saying they were struggling or couldn't hear me ! i was so fed up i rang Sony and did a "repair" with PC companion .. made no difference what so ever ! then it was fantastic, i was on the phone to phones 4U, who i bought the phone from, and the lady said "sorry i cant hear you sir" so the phone is going back. to be repaired . im not holding out a lot of hope that this will fix the problem due to the amount of threads where a fair few people are having this problem. seems to be a sub quality microphone on this device