It's warbled in Los Angeles (4)
I believe the answer is:
sang
'it's warbled' is the definition.
(I've seen this in another clue)
'in los angeles' is the wordplay.
'in' says the answer is hidden in the clue.
'SANG' is hidden in the letters of 'los angeles'.
(Other definitions for sang that I've seen before include "Did numbers" , "squealed" , "Chorused" , "Spilt the beans" , "Chanted" .)