Comedian with complaint adding nothing (7)
I believe the answer is:
groucho
'comedian' is the definition.
(I know that Groucho is a comedian)
'complaint adding nothing' is the wordplay.
'complaint' becomes 'grouch' (I've seen this before).
'adding' says to put letters next to each other.
'nothing' becomes 'O' (O resembles 0).
'grouch'+'o'='GROUCHO'
'with' is the link.
(Other definitions for groucho that I've seen before include "Funny man" , "One of Marx Brothers" , "One of Harpo's brothers" , "The Marx Brother with the moustache" , "A Marx; a club" .)