A client upset about right type of music producer (8)
I believe the answer is:
clarinet
'type of music producer' is the definition.
(type of musical instrument)
'a client upset about right' is the wordplay.
'upset' indicates anagramming the letters.
'about' means one lot of letters goes inside another.
'right' becomes 'r' (common abbreviation).
'a'+'client'='aclient'
'aclient' with letters rearranged gives 'clainet'.
'clainet' enclosing 'r' is 'CLARINET'.
(Other definitions for clarinet that I've seen before include "Source of music" , "musician" , "23 instrument" , "Instrument in claret, strangely" , "Find an instrument in claret" .)