Unsigned band’s music made money, to some extent (4)
I believe the answer is:
demo
'unsigned band's music' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe you can see a link between them that I don't see?
'made money to some extent' is the wordplay.
'to some extent' says the answer is hidden in the clue.
'DEMO' is hidden in the letters of 'made money'.
Can you help me to learn more?
(Other definitions for demo that I've seen before include "March (abbr)" , "Brass instrument valve" , "Public protest meeting" , "presentation" , "Eg, protest march" .)