Quiet tenant, one bringing joy (7)
I believe the answer is:
pleaser
'one bringing joy' is the definition.
(someone who pleases people)
'quiet tenant' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'tenant' becomes 'leaser' (I've seen this in another clue).
'p'+'leaser'='PLEASER'
(Other definitions for pleaser that I've seen before include "One satisfying" , "someone to whom gratitude is due" , "One trying to make others happy" .)