a bad connection causing high resistance in one of the joints between you and the cabinet
yes 2/3 more. Hub is connected in master socket. I know I need to get a filtered socket/microfilter, I'm just curious to know how my wiring is done for this issue to happen as I have two properties and in the other property this issue doesn't occur.
If you have no other sockets, and have connected to the test socket with a filter, and the phone is plugged directly into the filter, then the problem is external.
This is how you should test.
check wiring on removable bottom half- only terminals 2&5 are required and rest can be disconnected
What could it be? Well usually poor / corroded joints in your cable pair in junction boxes up poles or under manholes in the street.
Just like the bad joint that BT engineers have continually failed to locate in my phone line for the last 10 years, and which always plays up when there are big temperature fluctuations as is happening at the present time 😖