Sack members for unauthorised recordings (8)

I believe the answer is:

bootlegs

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

'for unauthorised recordings' is the definition.
I can't judge whether this definition defines the answer.

'sack members' is the wordplay.
'sack' becomes 'boot' (I've seen this in another clue).
'members' becomes 'legs' (leg is a kind of member).
'boot'+'legs'='BOOTLEGS'

Can you help me to learn more?

I've seen this clue in The Daily Express.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.