Pre-record pretentious stuff, a vocal item (7)
I believe the answer is:
cantata
'item' is the definition.
(I have seen 'Choral item' mean 'cantata' so perhaps 'item' could also mean 'cantata')
'pre-record pretentious stuff a vocal' is the wordplay.
I cannot really understand how this works, but
'stuff' could be 'tat' (I have seen 'Shoddy stuff' mean 'tat' so perhaps 'stuff' could also mean 'tat') and 'tat' is located in the answer.
'a' could be 'an' and 'an' is found in the answer.
The remaining letters 'ca' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for cantata that I've seen before include "Vocal composition" , "Vocal setting of a text (often religious)" , "aria" , "Short oratorio performed in concert" , "Vocal-orchestral piece" .)