I know we've seen this before (I [b]did[/u] search before I posted this [Linked Image] but I have a customer who's reporting that the bases of his bulbs keep getting corrosion on them.

He, of course, insisted that they must be getting corroded because of a lack of voltage... I explained that the corrosion most likely is causing voltage problems after it appears.

The fixtures are brass outdoor post lights, and yes, there is a drain / vent hole in the bottom (about 1/4") of each, and there was no discernable moisture in the fixtures when I looked.

Ideas?