I just started up my new 6300. I have the radio spectrum display. The icon changes when I check and uncheck the audio mute button and I can slide the level up and down and the little speaker button is blue and the slice (vertical) bar is yellow. I have no output to the power speakers on the back or to the phone jack in the front. I have searched through the manual but didn't see any other places where the audio would be muted. Ideas anyone?