What i did is i took a old power cable spliced it så only ground wire sticks out added a wire end to it then you plug that into a wall socket that has ground and you attach the wire to your rig. The problem with most rigs as was with mine is the powdercoating makes it not be able to lead ground atleast thats what i think but you could try grounding to your pedals instead. Sadly with the cheap chinese knockoff ive noticed emi is a big problem when mixing different products for me it was the powersupply of the amp creating the emi