Continuously feed speaker port (8)
I believe the answer is:
plymouth
'port' is the definition.
(port in Devon)
'continuously feed speaker' is the wordplay.
'continuously feed' becomes 'ply' (as in plying someone with food).
'speaker' becomes 'mouth' (you speak with your mouth).
'ply'+'mouth'='PLYMOUTH'
(Other definitions for plymouth that I've seen before include "Laughter my ploy (anag)" , "Mayflower departure, arrival port" , "The Pilgrim Fathers landed in USA on . . . Rock" , "where sailors found" , "Devon port city" .)