Whirring noise at start and stop

[Euro5stars]

Bought a 98 XJ8 3.2l in July. Can anyone tell me the noise that occurs at start up and then again after switching ignition off ('bout 2-3 seconds). It sounds like it should be the aerial motor, but it isn't, as that happens some time after and is it at the back, and sounds like it comes from near the steering and behind the dashboard. Everything works, I think, unless someone tells me something is about to drop off.

[chris.mapey]

My XJR does the same - been told its the motors opening the vents in the heating system when you start the car...

[Euro5stars]

Cheers. Didn't sound terminal or 'wrong' just odd. Ta