I've had this unit for about two years and in two cars. Great HU but all of a sudden it will freeze when I push the buttons (not letting me change the song, station)Or turn off when I push the buttons. It also turns off if I push on it any where. I'll have to pop out the face then pop it back in for it to work, sometimes that doesn't work. Any thoughts on this besides getting a new HU. I'm a poor college student.