Stall rate increase (9)
I believe the answer is:
temporise
'stall' is the definition.
('stall'->'temporize' is in my internal thesaurus and 'ize'->'ise')
'rate increase' is the wordplay.
'rate' becomes 'tempo' (tempo is a kind of rate**).
'increase' becomes 'rise' (rise is a kind of increase).
'tempo'+'rise'='TEMPORISE'
(Other definitions for temporise that I've seen before include "Delay" , "fail to decide" , "Hedge" , "Put off" , "Emptier so as to avoid giving a definite answer" .)