Within minutes, idiot adviser rebuffed radio and the press etc (4,5)
I believe the answer is:
mass media
'radio and the press etc' is the definition.
(radio and the press are forms of mass media)
'within minutes idiot adviser rebuffed' is the wordplay.
I cannot quite understand how this works, but
'minutes' could be 'm' (common abbreviation) and 'm' is found within the answer.
'idiot' could be 'ass' (I've seen this before) and 'ass' is present in the answer.
The remaining letters 'media' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
(Other definitions for mass media that I've seen before include "Press, TV, etc" , "Papers, TV, radio, etc" , "Agencies of public information" , "TV, radio, press" , "Purveyors of news" .)