Flute? Part played is routine (10)

I believe the answer is:

mechanical

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'is routine' is the definition.
(mechanical can mean automatic or routine)

I don't understand the rest of the clue.

(Other definitions for mechanical that I've seen before include "Automatic" , "Bottom perhaps" , "Machine-like" , "Lacking thought or spontaneity" , "Robotic" .)

I've seen this clue in The Guardian.

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