today i was listening to music in my pre when i recieved a call and disconected the headset, answered the call and everything was ok..but the next call i recieved i couldnt hear the person..when im on a call the screen doesnt turn off anymore and the volume icon appears without any blue bars..like if it was at the minimum and i cant fix it..its the same with the music..i hear the music low and cant put the volume up..any help please