I also had the same issue. One time my touch screen was replaced. For couple of months it was fine and then again started the problem of touch screen issues. It automatically pressing buttons and some times doesnt work at all. And those are totally random.Any body from Sony, why dont you introduce a softare upgrade to use all functions using keyboard. At least this would have been made us to use the phone. But as of now most of the functions required touch screen and you do not have key sequences, thus my phone is becoming useless.
