Arrange American music for film to pay someone back (6,1,5)

'film to pay someone back' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'arrange american music' is the wordplay.
I cannot really understand how this works, but
'arrange' could be 'settle' (settling is a kind of arranging) and 'settle' is found within the answer.
'american' could be 'a' (common abbreviation - e.g. in organisation names) and 'a' is found in the answer.
'music' could be 'score' (score is a kind of music) and 'score' is found in the answer.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).

'for' is the link.

Can you help me to learn more?