Had them for about a year now. When I turn it on it lights up fine, but consistently after about 5 secs the flickers and shuts off. I'm thinking it's the bulb but if there was a problem with the ballast would it do this? It turns off after 5 secs of light-up time consistently and predictably. I'm supposed to swap ballasts to see but the ballasts are in very difficult to reach places and I'm thinking of just sending back the bulb for warranty. Thanks!

 

happened to me. Turned out to be the ballast. got a new set.

 

Thanks man, I found out it was the ballast.