Orchestral passage: sound of annoyance with it backfiring (5)
I believe the answer is:
tutti
'orchestral passage' is the definition.
(I've seen this before)
'sound of annoyance with it backfiring' is the wordplay.
'sound of annoyance' becomes 'tut' (I've seen this in another clue).
'with' is a charade indicator (letters next to each other).
'backfiring' says the letters should be written in reverse.
'it' reversed gives 'ti'.
'tut'+'ti'='TUTTI'
(Other definitions for tutti that I've seen before include "Orchestral passage" , "All performers (mus.)" , "with instruments and singers together" , "With all playing together (music)" , "Everybody (mus.)" .)