I think this is the first disappointing experience I've had with an OR engineer on a visit.
The crackling did come back since my last post, which I was thinkful for so it could be heard.
The engineer got here and assumed it was the master socket that was causing the problem, a known issue apparently. It was the socket with the 2 connectors top (broadband) and bottom (phone line).. and so she changed it to the mk4 master socket with the 2 connectors side by side. I'll post a picture of one
similar to it that I got from an online source.
So she left and we assumed everything would be fixed. But just had a phone call and the crackling is as bad as ever. It is so bad it can be heard just by picking up the phone and listening to the dial tone.
I don't understand how she can have come to the conclusion that the problem was caused by a faulty socket when I'd done the check through the test socket. Maybe she was guessing or something?
So the problem isn't fixed.
I noticed in the email BT send out they assume the problem is fixed and don't ask if its fixed. So I'm going to have to be making another appointment soon