Loud leftie: "stop working, man!" (7)
I believe the answer is:
freddie
'man' is the definition.
(I've seen this before)
'loud leftie stop working' is the wordplay.
'loud' becomes 'f' (short for forte - 'loud' in music).
'leftie' becomes 'red' (red can informally mean a political leftwinger).
'stop working' becomes 'die' (I've seen this in other clues).
'f'+'red'+'die'='FREDDIE'
(Other definitions for freddie that I've seen before include "- Mercury, rock singer" , "man" .)