All audio stops working on the phone suddenly, for example I cannot hear the person when I make a call not even via speaker phone or via the headphone. Music will not play, no noise or vibration when calls ring. I tried to reset the phone, the problem persits. I did software repair via Sony companion still the problem perists. When I re start the phone it may work sometimes for a few hours without any issues and at other times it would not work (audio). I deleted all applications and used still the problem persits. What can I do?