Tell you what, the round pegs you cleaned are silver plated. They are not the problem. The problem is inside the switch. You have to uncrimp it, dig out the old thick grease, wash it, polish the contacts, replace the grease, and recrimp it. Don't get an emery board near electrical contacts. It leaves small particles of hard (emery) rocks that don't conduct electricity embedded in the soft silver. Or just replace the switch.