I have a dd cpx pro pump and I just finished installing my wc setup. When I turn the pump on with the res completely full it makes a weird cycling noise and the inlet is barely pulling water from the reservoir and its going extremely slow, its more like a drip than anything, the tube is not even filling up with water completely from the res to the pump, its trickling down the tubing to the pump. it looks like its actually pushing water out of the inlet side. I have the 3 pin connection hooked up to a molex connection on the psu. any idea why its doing this? Do I have a bad pump?