Turn up aircon and perform vocal cover (6)
I believe the answer is:
casing
'vocal cover' is the definition.
'casing' can be an answer for 'cover' (I've seen this in another clue). I'm not sure about the 'vocal' bit.
'turn up aircon and perform' is the wordplay.
'turn up' says the letters should be written backwards.
'aircon' becomes 'ac' (I can't justify this - if you can you should give a lot more credence to this answer).
'and' means one lot of letters go next to another.
'perform' becomes 'sing' (to perform a song).
'ac' back-to-front is 'ca'.
'ca'+'sing'='CASING'
Can you help me to learn more?
(Other definitions for casing that I've seen before include "Protective covering as of engine" , "Protective shell" , "Outer covering of something" , "Recceing" , "Outside cover" .)