Hi, i've had my pioneer pdp434hde for two weeks now and every now and again it goes light then dark, light then dark, light then dark and so on. Do you think this is a problem with the set or to do with some of the settings. It happened when i first got it, then stopped (but i have been messing around with the settings a lot) then i noticed again today. Apart from this i am very happy with the TV. Thanks Mark.