Labour's demise always on the radio (9)
I believe the answer is:
endeavour
'labour's' is the definition.
(endeavour can mean a labour or effort)
'demise always on the radio' is the wordplay.
I cannot quite see how this works, but
'demise' could be 'end' (I've seen this in other clues) and 'end' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for endeavour that I've seen before include "Enterprise; earnest effort" , "Cook's old vessel" , "Make a serious effort" , "Aspire; attempt" , "Expenditure of effort" .)