Need disheartened reggae singers on the radio (7)
I believe the answer is:
require
'need' is the definition.
('require' can be a synonym of 'need')
'disheartened reggae singers on the radio' is the wordplay.
'disheartened' says to hollow out the word (remove centre letters).
'singers' becomes 'choir' (I've seen this before).
'on the radio' shows a homophone (sound like).
'reggae' with its middle taken out is 're'.
'choir' sounds like 'quire'.
're'+'quire'='REQUIRE'
(Other definitions for require that I've seen before include "Need" , "exact" , "Insist on" , ".. must have" , "26 [ORDER]" .)