High Revs>?

Hi there I have a 97 Disco 300tdi auto and it seems to be revving quite high. In neutral it is revving at around 1000 rpm and also the gears seem to be changing a little slow for some reason.
I've had land rovers all my life ranging form series to 90s and range rovers but this is my first disco.
It also has a million other issues (as discos do), but I thought I would start with this issue first.
Any ideas or advice?
Many Thanks

Mine suffered from a loose kick panel which would catch the pedal so it wouldn't shut off fully - revved at 1,000rpm. Got fed up and cut a 2 inch/ 45 degree chunk off it. Ain't done it since.

Just a thought.

What speed does it change gear at? Somebody on here will know the correct speed/change.