We have tested this with an input via the guitar input and the unit is working BUT the Tape/Cd in input and volume have a problem, the volume control for that input is faulty, noise comes out the speaker when nothing is attached, moving the cd in volume control or tapping it can stop it happening, also any input via the Tape/Cd input outputs at max volume no matter what the volume control is set to, so that volume switch has a problem, may be faulty or maybe dirty contacts, supplied with mains lead