Gosh darnit there are some things that thumping should fix (candy machines) and some things that should be scientifically fixable.
So this cheapo flo light with electric ballast comes on 50% of the time. 100% if you give it a little thunk. Swapped the tubes. No change. Rotated the tubes a little and that improved the reliability for a day. I'm guessing bad contacts, but is there any way the ballast could be at fault here? I have no idea what the age of this thing is.