I have a 90 st. my radio wont turn on. when i turn the volume up to max, i can still hear something but its really faint. even when my keys arent in the ignition i can still hear it on. i cant even change the channel. if i turn the volume to min, i dont hear anything. my battery is fairly new so i dont even know. that same day it was workin fine. does anybody know whats up?