I found the master socket and unscrewed the lower half of the faceplate to get to the test socket. At this stage I noticed two things: the master socket was hanging off the wall and there were two extra wires going in to the back of the socket. One was to a socket that the router was plugged into and the other was to internal wiring to at least one extension socket.
Disturbing the master socket has dropped my sync speed from 2048/448 (slow but stuff worked) to 1120/448 where applications get time-outs. Finally, we're rumoured to be getting FTTP next year at which time this will, I hope, become irrelevant.
So I conclude that a previous owner has gone for some cheap and nasty wiring rather than having the job done properly and now I'm stuck with it. I either live with it or get BT to sort it.
Now my question. Is this likely to be covered by the £129.99 engineer call-out that I see on the BT website? At one time I seem to remember that BT wouldn't charge if it was rectification of bodges by a previous owner but I'm not holding my breath for that.
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