2001 Headlights going out

I have a 2001 Suburban that the automatic headlights keep going out. Sometimes they will work on bright but not dim. Sometimes they will work and then go out while driving. Anybody had this problem.
Thanks

I have the same problem 2001 Yukon. First noticed it about a year ago, only happened once in a while...now it's all the time. When I try the override everything works but the low beams?? The switch is easy to change but costs $60 and I don't know if thats' the problem. If I don't get an answer I may just run a wire and jump the low beams to the fog light and use the manual override.