I have two post mounted outdoor lights on either side f my driveway. They are relatively new- one around 2 months, the other just over a year. The oder one works fine. The newer is a replacement for one which had problems after about a yearand now tthe newer one is showing the same symptoms. They are LED fixtures. What happens is the problem one(s) appear to need a long time to come to full brightness and sometimes never seems to ever get there. Incandescent fixtures at the site had no problems. Does anyone have any insight to this??