Tick-over rising when Hot- 7A

[Crossle]

Small problem that doesnt bother me too much but it its an easy fix I would certainly get it sorted- If I start my car from Hot (2.3 20V 7A engine) the revs rise by around 250rpm on tick over and stay there- it doesnt fall back to normal tick over for some reason. I would say overall the revs are more sticky throughout the rev band as well, when I change gear the revs fall away really slowly so end up slipping the clutch constantly. I've set the standard tick-over at 950 but on a hot re-start its more like 1200. This is only if I switch the car on and off again- if the car is kept running while hot then its not a problem. Mainly presents a problem when I stop for fuel- when I get back in the car and drive off the revs are sticking.