Hi and thanks for your reply ,
The caps dont have any bulging or leaks , and i dont think it a problem with dirty pot controls either .
The crackling sound just comes with power outtake , at really low volume its ok , nothing more when adjust the pot controls.
What do you mean , What is the Amp module they use in the amp?
I know it is a 300-325w bash amp ( the one witrh built in crossover).