My next door neighbours had a voice fault the other day (they don't have broadband.) From the external junction box a cable feed their NTE5. The Openreach engineer tested the line from the external junction box to the cabinet/exchange and found that it was OK. So the problem was with the feed from the external junction box to the NTE5 but it was virtually impossible to locate due to the routing of the cable. So he fitted a new NTE5, plus a new cable, closer to the external junction box which involved drilling a hole through the exterior wall. He left the original wiring and old NTE5 in place because to have removed them would have caused disruption to furnishings/carpets/decorations/paintwork.

If they had broadband then he may have supplied a filtered faceplate, used an existing filtered faceplate (if it was deemed not to be faulty since the fault was found from the test socket) or simply continued with the original setup with dangle filters.

All this work was, or would have been, booked and the in the case of my neighbours there was no charge for this work since the problem was exchange side of the old NTE5