Superstar's not working for the audience (4)
I believe the answer is:
idol
'superstar's' is the definition.
(thesaurus)
'not working for the audience' is the wordplay.
'not working' becomes 'idle' (I've seen this before).
'for the audience' indicates a 'sounds like' (homophone) clue.
'idle' is a homophone of 'IDOL'.
(Other definitions for idol that I've seen before include "Film star" , "Much-loved actor" , "Figure of worship" , "Sacred image" , "Superstar; graven image" .)