My Question is , I have a 2009 FWC Hawk, when I plug in the shore power cord there is a spark / snap when I plug in the extension cord. I purchased a polarity tester and it reads that the outlet is functioning properly. In addition I tried using different extension cords with the same spark/ snap. The lights, refrig, fan,water pump all seem to work properly, but Im concerned that I may cause damage. Thank you for any assistance.