Air on with AC needing fix — something blown (7)
I believe the answer is:
ocarina
'something blown' is the definition.
(ocarina is a kind of wind instrument)
'air on with ac needing fix' is the wordplay.
'with' means one lot of letters go next to another.
'needing fix' indicates an anagram (I've seen 'needs fixing' mean this (I've seen this in other clues)).
'air'+'on'='airon'
'airon' after 'ac' is 'acairon'.
'acairon' with letters rearranged gives 'OCARINA'.
(Other definitions for ocarina that I've seen before include "Simple wind instrument" , "Egg-shaped type of flute" , "Small egg-shaped wind instrument with holes for the fingers" , "Toy flute" , "Primitive wind instrument" .)