Switch end, playing (6)
I believe the answer is:
button
'switch' is the definition.
(button is a kind of switch)
'end playing' is the wordplay.
'end' becomes 'butt' (I've seen this before).
'playing' becomes 'on'.
'butt'+'on'='BUTTON'
(Other definitions for button that I've seen before include "Jenson --, Formula One driver" , "On-screen control" , "Tot bun up for a fastener" , "Tot bun up for a fastening device" , "Fastener to fit through a hole" .)