Rewarded for quiet help (4)
I believe the answer is:
paid
'rewarded' is the definition.
(I've seen this in another clue)
'quiet help' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'help' becomes 'aid' (synonyms).
'p'+'aid'='PAID'
'for' is the link.
(Other definitions for paid that I've seen before include "Forked out" , "Gave money for goods or services" , "Hired" , "Handed over money" , "Settled debt" .)