Uneven volume taper - have I wired this correctly?

After one of many mods my tele volume pot seems to have a very uneven taper - the first quarter turn puts the volume at about 10%.

I think it was when I changed it to 50s wiring, but I've now changed it back and there's no change. I don't think I changed the pot. The one that's there now is a 250k audio pot -and I think that's what it should be, right? I think the tone pot is the same but much of the writing is obscured.

Over the last few days I've tried a few different wirings, but no change.

So could it be the pot? Or something else in the wiring? Diagram below (I've got texas specials and a 4 way switch at the moment, hence the extra wires. The issue I'm having pre-dates the installation of the specials).

Any suggestions?

http://www.theseveninches.co.uk/pics/telediagram.gif

Ok so I just measured the volume pot. It's 216k at full (it's a 250k pot) and at halfway it measures 191k. That doesn't sound linear. Does it sound right for a log pot?

Pots aside, does anything else look wrong? I might just have to rip it all out out and start again.

The Secret Life of Pots (http://www.geofex.com/Article_Folders/potsecrets/potscret.htm)