On my Ibanez SG 655 when in active mode, will make the speakers on my Little Mark IV combo Amp thump in & out violently, but not all the time. Just once in awhile. The other night it did it when I turned up the mid know. Fine at half way, but got worse as I turned it up. This bass also seems to have way more output then it should in active mode. Any ideas on how to approach this?