I got a rumble 100 that cuts out when hitting low end notes every time, Starts out with some crackling then sound subsides. The amp stays on, red light indicator stays on and red lights at the bottom also stay on when switch is on from the back of amp. If I connect via cd input jack and play something that has low end same thing happens, only time amp performs as normal without any cut out is when I have headphones plugged into it. Any help would be greatly appreciated, thanks in advance.

Music - Fender - Rumble 100 Bass Guitar Amplifier