They could have found that the lead in was faulty. I once rang Telstra to complain about my phone and internet and they sent someone out who found that the lead in cable from the pit to the townhouse block had something called 'battery'. A contractor was sent out to replace it and he reported that it had been done and presumably he was paid. I then complained that there had been no improvement so a second tech was sent out and she found that the contractor had not replaced the cable and instead connected a couple of spare wires from the lead in cable to my townhouse. The lying bastard was dishonest and thought he'd get away with it. When the lead in cable from the pit to the building was changed the problem was fixed.