I've got a package 6 2006 Prius. One of the headlights keeps going out. I can't really tell when or how it goes out since I can't see it. I'll notice it when I see the reflection in the back of another car. If I turn the bright lights on and off it has no effect, but when I turn them all the way off and back on the light comes back. Sometimes on long trips it will stay on the whole time, sometimes it won't. Sometimes on short trips it will go out, sometimes it won't. It is not an event I can make happen. I've taken it to the dealer and they can't make it happen (of course). ANyone have any ideas as to what is going on?