Plumbing problem
I believe the answer is:
'plumbing problem' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for drip that I've seen before include "Splash - softie" , "Dribble" , "Fall in small drops as from wet clothes" , "Intravenous administration of solution" , "Fall in small drops as from tap" .)