Crossword Genius

They're at home in American vocal music (3,5)

Ross

I believe the answer is:

old folks

I'm a little stuck... Click here to teach me more about this clue!

'they're at home in american vocal' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'music' is the wordplay.
I cannot quite understand how this works, but
'music' could be 'folk' (folk is a kind of music) and 'folk' is present in the answer.
The remaining letters 'olds' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...

Can you help me to learn more?

I've seen this clue in the Evening Standard.
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