Tune; broadcast (3)
I believe the answer is:
air
I believe this clue is a double definition.
'tune' is the first definition.
(air can mean a piece of music)
'broadcast' is the second definition.
(synonyms)
(Other definitions for air that I've seen before include "Atmosphere surrounding us" , "- brick; - bed; - brush" , "Broadcast; express" , "Bearing, manner" , "Cause of inflation" .)