crackle and static in my colloseum 300

[AMPS]

i posted a message re: this amp previously and took care of or my ocillating feedback loop (thanks Don T.)

I have now discovered that the amp has a additional problem.
when playing through the amp with a bass guitar crackle and sometimes static occure in the signal. it is really apprent on low notes A or low E strings. sometimes static remains when not even playing the strings.
and even sometimes when the bass is unpluged from the unit.
i have checked the amp with two other cabs and speaker cables. the problem persists.

i am not sure where to check. is it a power cap issue? the amp has traveled and been smacked around a bit.

thanks.

[JoeArthur]

Sure sounds like dirty controls to me.  Try to remove the static/crackle sound by moving a couple of controls... if it goes away, spray them with a good control cleaner.