I am in need of some help with my BCT15. For some reason, there is absolutely no sound when someone keys up on a channel, even with the volume as high as it will go. The only way you can hear anything is when you plug in headphones into the jack on the scanner. I figured if the speaker was busted, I would still be able to hear something, it would just be muffled. What am I missing? Can anyone help me out?