In reply to a post by Garyilka:

When I went to Infinity a couple of months ago the BT engineer tested the ADSL Nation faceplate I already had and left that, saying it was as good (or better than) the BT one...........

The problem though is that the OP wants to run the modem off an extension which is wired unfiltered from the back of the Clarity faceplate he has.

So he does - I overlooked his post expaining that and still had his first post in mind which seemed to describe a straightforward faceplate installation! Sorry about that

Thanks for all your helpful suggestions on this so far. Assuming that my cabinet -- and not just the exchange -- are upgraded this September, I'll keep my fingers crossed for a helpful BT Engineer who's prepared to take a sensible approach to this and not change things for the sake of it.

In the meantime, does anyone know where/how I can find out if my cabinet is on the list to be upgraded?

Given your post code several of us can check cabinet(s) for it as at April, and if that looks dubious there is a later list as well.

Thanks, RobertoS - I've PM you my postcode.