I have a MTX jh1200 amp..and it comes with a "bass knob"..Im sure who ever is reading this knows what that is. When i turn the car on, or the ignition, the light on the bass knob by my seat lights up..like it should. but the power light on the amp doesnt light up blue. but it still powers my subs fine. and the cooling fans on it arent moving either when its on. is this common? should i be concerned? just wondering.