After passing the voltage tests I used my newly assembled crack for about an hour. When I went to unplug my headphones from the crack I put one hand on the chasis plate and the other on the half inch plugg (metal). I had the volume down but the amp was still one (seeing as the volume control just affects the input When the plugg was most of the way out I recieved a significant zap through my hands. Is this normal (cant say I have ever tried holding a grounded plate while removing the jack on any other device) or is there something seriously wrong in my wiring? If it maters when I did the voltage tests there was a constant 15mV reading on the chasis.