Sounds like your t/p line is being affected by water in the junction box outside the house or the connection at the top of the pole (if there is one). Can you get to the box to make sure the terminals are clean and no water is getting in. Could even be that the line is damaged in some way and allowing water in.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.
I think i may have traced the fault to a neighbours recently built extension. The muppet that built it has put all the phone wires from approx 4 houses across the flat roof. If i remember right roofing felt is like sand paper. I bet the phone line has been rubbing on the edge of the roof causing it to have no insulation at that point. Who is responsible if this is the case?
I think the safest way out of this is a complaint to BT pointing out to them the possible problems with your line running over a flat roof. That way you don't get aggro with your neighbour and BT take up the fight on your behalf.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.
Just ring BT or whoever supplies your phone line and take it from there. A few years ago when I lived in a rented house someone had replaced fascia board under the window and pulled out phone wire & left it swaying in the wind, bad weather also affected that, called BT they came out & replaced it with new cable and secured it back in place straight away no questions asked.
-------------------- If I can't be a good example, I'll just have to be a terrible warning