Acker --, clarinettist with hit 'Stranger on the Shore' in 1962 (4)
I believe the answer is:
bilk
(Other definitions for bilk that I've seen before include "fleece" , "Defraud; Acker --, clarinettist" , "Cheat or defraud" , "Cheat (of payment)" , "Acker --, jazzman" .)