Rattle record playing? Sure thing (10)
I believe the answer is:
disconcert
'rattle' is the definition.
(thesaurus)
'record playing? sure thing' is the wordplay.
'record' becomes 'disc' ('disc' can be a synonym of 'record').
'playing?' becomes 'on'.
'sure thing' becomes 'cert' (I've seen this before).
'disc'+'on'+'cert'='DISCONCERT'
(Other definitions for disconcert that I've seen before include "Disturb, unsettle" , "Bother" , "upset" , "Throw" , "Shake up" .)