Awful noise, always ignoring volume -- that's criminal (9)
I believe the answer is:
racketeer
'criminal' is the definition.
(racketeer is a kind of criminal)
'awful noise always ignoring volume' is the wordplay.
'awful noise' becomes 'racket' (I've seen this before).
'always' becomes 'ever' ('ever' can be a synonym of 'always').
'ignoring' is a deletion indicator.
'volume' becomes 'v'.
'ever' with 'v' removed is 'eer'.
'racket'+'eer'='RACKETEER'
'that's' acts as a link.
(Other definitions for racketeer that I've seen before include "someone on the fiddle" , "Wide boy" , "someone to make a dodgy deal?" , "Capone, for one" , "tennis player?" .)