One's played character in Shakespeare play (5)
I believe the answer is:
viola
This clue is a double definition.
'one's played' is the first definition.
(viola is a musical instrument)
'character in shakespeare play' is the second definition.
(character in Twelfth Night)
(Other definitions for viola that I've seen before include "Sebastian's sister" , "String instrument of a range between the violin and cello" , "Cesario when in drag" , "part of a broken-down 27 [CARTHORSE]" , "big fiddle!" .)