While stopping for a second the other day I noticed that if the transmission is set to 'Park' then it fails to stop the car rolling if on a very slight incline. The movement is accompanied by a sort of clicking noise that sounds, and probably is, some sort of pawl failing to engage in a cog. In all other respects the vehicle seems to work OK. (Apart from occasionally losing power on roundabouts - but I'm 99.9% sure this is a separate issue)

Any thoughts?

(I might post this on the Disco forum too as I assume they are also liable to the same issue)

I think your diagnosed exactly the issue. not common at all, but can happen on autos. Either use the handbrake and live with it, or it may need taking apart.
Of course also check that the gear linkage is freely moving and greased up on the side of the gearbox. Could be that it's just not able to go fully home due to corrosion. Bodsys Brake Bible
Software Updates Contact me
RRS Timed Heat/Remote kits - Contact me
BAS Engine Re-maps/ EGR Blank EuIII and EuIV
Clock On The Dash/ SNOTM /3Flash / BT Update /Service Reset/Error Codes read\ Gearbox Reset
See it HERE

That's very helpful. Thanks!

There is a TSB for this.

A problem with the ZF gearbox manufacturing.

Thanks - Is there a link to the TSB or some way of viewing it?

Publication No. A023

Having read it, it only effects 2005 and 2006 cars.

Vin (sport) LS 916973 to LS 924895

parking pawl guide plate to be replaced

If you want a copy, PM me your email address

There is this one but refers to very early cars.

http://www.theaa.com/allaboutcars/recalls/...;makeId=C3

Cheers
Col

Hmmm - Sounds like the TSB may not be applicable. Bizarrely, the problem seems to have corrected itself the last time I tested it. I'll see how it goes before I get the garage to dismantle the entire gearbox!