Speedometer and automatic transmission problem

intermittent fault on speedometer when engine hot speedometer would drop from 80km to approx 30 to 40 km then return to normal after a few minutes. also, the cruise control makes the engine rev up and down when the odometer goes wrong. changed speed sensor, still have fault.Auto gear box also has intermittent fault when hot some times will not change to the correct gear, one lower then normal will only go into top if I manual use the sport shift.on return to normal drive will stay in top but when need to change down in drive position will not always go into the correct gear unless I put it sport mode again.