OK thanks - now we get into the area where I cannot help much.
But in the rest of this post you help a lot
. Don't under-rate yourself.
The flat is new and was wired by a telecoms company but not BT.
Until last week there was no "Master Socket" at all.
Wire came in from a "comms" building and fed into a surface box on the wall from which it seems all wires leave to all over the flat from a load of punch down connections.
Openreach interrupted the incoming wire to fit the Master Socket last week and from there the feed went back in to the multi wired box.
As the BT engineers say, not ideal, but not likely to cause the problem you have.
I was worried about six wires into each of the relevant connectors on the faceplate.
Cable joint accidentally disturbed whilst connecting some one else? I don't know. Could a dodgy joint cause this?
That I don't know sorry. I was purely worrying about the star wiring, which as I said would have been a severe problem if the exchange side of the test socket, and these little IDC connectors on the faceplate if they had six wires each in.
Nothing is connected to any extension sockets - just the Hub5 and phone on one socket with a filter. And even when I separate these there is no difference to the problem - also I can remove the hub completely and still there is a whistle on the line.
To me that sounds as though Zarjaz's contribution stands a chance of being the next step. Though a couple of thoughts:
1) Are you always using the same phone wire to connect between the phone bases and the master or test socket? If so, try a different one.
2) (This one is unlikely but I want to rule it out). Are you also using a plug-in phone extension cable to reach the master, instead of just a standard short wire?
Kindness isn't going to cure the world of all its awfulness but it's a good place to begin. Daisy Ridley.
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