I pull the bulb out and put a small dab of clear silicone on each side of the bulb just above the wires and then reinsert it in the socket. The silicone actually bonds to the the chrome shield of the spotlight and doesn't interfere with the wiring. If you ever need to remove the bulb the silicone peels right off. I use Permatex clear RTV. Hot glue works as well but will pull the chrome off the shield if you ever remove the bulb.