FYI - my "slim ballast" Xentec kit experienced the same problem. I think its because, for whatever reason, that kit needs a relay. The flaring (it was in the passenger side bulb), continued - and after a while if you looked closely, that bulb was always constantly flickering slightly. That bulb or ballast ultimate kicked the can (I didn't check which one). And I replaced the Xentecs with the original China regular ballasts. No flaring even since.