Just checked to see if you solved the problem, I was away. Only last thing I can think of is it may be an overheating issue. I had this problem when my burner was in the top of the tower and a hard drive tray was directly under it, all air flow was blocked. Probably not your problem but if you have around a 6 inch fan place it blowing directly on the burner, make sure air can get at the bottom of the burner where the electronics are, it may just be a problem with the burner.