I have seen the condition described many times, and corrected it by putting in a new switch. Recently I realized that if the switch is bad it could happen while the plane is in the air and cause a crash. I now use better switches. They have gold contacts, heavier wire, and cost close to 3 times more. I'm expecting to get much more life out of them so the added cost is not a factor. I'm happier and that is what counts.