1999 Jaguar XJ8 Excessive cold start cranking

when the car sits overnight the first start up of the day takes about 3 to 4 seconds of cranking regardless of air temp outside. After the first start up of the day the car fires right up within 2 seconds of cranking. What could be causing this first start of the day to have to crank so long to start. the car runs fantastic but that first start of the day seems to be excessively cranking to fire up. it fires up nicely to, o issues with it dying out or anything like that but is does have a slight rough idle upon starting up then smoothes out within 15 seconds, idle is at the correct rpm's as well.