I recently switched a handful of G4 based bi-pins for a customer in some puck lights from halogen to LED. The color is great, less power, etc.,etc... However, the pins are a hair smaller than the original halogen pins, and some of the lamps are loose enough that tapping the fixture causes a couple of them to blink on and off. I tried some socket grease, but it didn't help. My next move was going to be a dab of silicone on the back of the LED board to hold it in place. Anyone have any better ideas?