We have a BT 3505 digital 3 phone system. The master phone is in the
dining room, a slave phone is in the lounge and the third one is in our
bedroom. (Until recently, we have both been on call 24/7)

The BT telephone cable terminated under the stairs and I ran an
extension to our old phone around the floor, hidden by the carpets.
Due to various changes to the flooring, I am unable to do the same again.

No problem thought I, I'll run it around the ceiling where the eye does
not often travel. In the mean time I slung up a 10 M. extension over the
doors till I could get a round tuit. The other day, I bought a 20 M
extension because I couldn't source a 15 M one. The total wire length
would have been about 10 to 12 M.

Now comes my problem.
After drilling a hole in the wall and passing the plug towards BT's
socket, I pinned it up to run along the ceiling to the socket in the
lounge that shares the internet router and the master digi phone. I used
my mobile to test the line. All was well.

I woke this morning to find a note from my wife, saying that the house
phone was giving the message that the number called was not recognized.
Lo and behold I got the same :-(
Switched back to the 10 M line and everything works fine.

Is this because...

1 I have coiled the excess cable (about 7 M) and slipped an elastic band
around it. Yes, I am aware that they should be twisted pair, but I
suspect, due to the style of cable, that they are not, because I can't
find any cable clips that are small enough to hold it to the wall. But I
could be wrong. Extension is of the type that you can buy anywhere.

2 The cable is now too long for the digi phone.

3 the BT digi phone can not get through the coiled wire.

4 the digi phone can not get enough signal to the BT inlet, because of
the length of extension cable.

Any ideas anyone?

TIA

Dave