Autogearbox

Hi there,I have a 1997 clk 230 kompressor sport,when the car is started for the first time in the morning,I have to wait for about 10 minits before I drive off so that the gears will change properly,if I dont let the car worm up first when I drive off it holds in the gears and dosent change verry soothly,apart from when I first have to do this when the car has been left more than a hour at a time it runs grait,eney idears enyone.
thanks for eney input much appreciated.
iceiceice.