A very strange broadband problem

Im_just_careful

I can generally get to the bottom of a datacoms problem but this has me very puzzled.

My inlaws live in an old house with plenty of phone sockets (although only 2 phones) and have recently moved from dialup to broadband.

Sadly the broadband modem "holds the line" and makes the line think the phone is "off hook" so incoming calls get the engaged signal.

BT have tested the phone line and that checks out (there is a point of disconnection to unplug the house wiring) but I find it difficult to explain what I have observed. I've tried a different modem (which works fine at my house) and it is still the same.

This problem also seems to take a while (few minutes to an hour or more) to manifest.

I've tried various filters but I haven't yet taken all the bell wires off the sockets.

I've not (yet) had the carpets up, the floorboards up, found all the joins underfloor and had the whole thing apart and built it back up from scratch but it seems that I may be doing this before long.

Before I spend a very distructive day at their house does anyone have any suggestions ?

spannerzone

assuming all the extensions start from the master socket you only need to remove the ringer '3rd' wire at that point and unless they have any old phones that require the ringer voltage then it won't matter.

I'd try this first as it's one easy check (assuming there is an NTE5 style master socket)

The things I've found cause odd problems are:
poor extensions that have lots of spurs running all over the place maybe with twisted wire extensions,
extensions that use that really thin DIY flat cable (the stuff they sell for easy DIY to hide under skirting/carpet),
ringer wire causing odd behaviour, especially if modem connected to an extension socket.

My aunt had a similar sounding issue, when we connected their ADSL modem to an extension socket it made the phones all ring so I removed the ringer wire and problem solved.

macman

First thing that you need to do is to run the test from the BT test socket behind the master socket split faceplate (if it's an NTE5). If no NTE5, run it from the master socket with everything else disconnected and see if OK. If it works, then reconnect one by one until you find the fault.
If the fault is still there from the BT test socket, then you need to get BT back (preferably a OR broadband engineer rather than the standard line engineer).

spike7451

It's one of two things,either the line card in the exchange or,most likely,it's the phone itself.