Hi, i recently built my anet a8, but i have a strange problem. the power supply works while there is no power to the main board, but when there is, I plug in the plug to the wall, it sparks, which means it is somehow not grounded. The LED on the power supply lights up for a split second before going out. Then i unplug it, no sparks, and the led flashes again then shortly after there is a small noise coming from the power supply. I've checked my wiring at least three times, still does the same thing. Was my board DOA?