My lamp the Chinese one always has a plug floating at the top after I shut it off. No probs. I wait till its cool and give it shake to break water tension and it goes to the bottom. But I come back and its back at the top again. This must be because of it being so close to the buoyancy of the water and when the water cools to the point that the wax is lighter it goes back up. Anyone see this? I have seen it at the top and shaken it lightly to make it fall but never seen it rising.