Instrument that makes money for the listener (4)
I believe the answer is:
lute
'instrument' is the definition.
(lute is a kind of instrument)
'money for the listener' is the wordplay.
'money' becomes 'loot' (loot is a kind of money).
'for the listener' indicates a 'sounds like' (homophone) clue.
'loot' is a homophone of 'LUTE'.
'that makes' is the link.
(Other definitions for lute that I've seen before include "Plucked, pear-shaped instrument" , "Ancient stringed instrument" , "Elizabethan stringed instrument" , "instrument that minstrel played" , "Old guitar-like instrument played by minstrels" .)