Higgs Boson wrote:

Thanks for suggestions. I can't see why a fixture only 3 years old
max would have a loose ballast. Nobody goes near the fixture; it just
hangs up there. I don't know how to replace a ballast, (a), and (b)
the cost might exceed just getting a new fixture.

Feedback?


If your hand fits a screwdriver, it's a simple enough job to tighten the
screws and see if the hum goes away.

If a new bulb won't light, you may have a defective ground.

To replace a ballast, take the old one to a box store and tell the clerk you
want to replace it. Five out of seven times he'll give you the right one.
Wiring instructions come with the ballast.