So I mailed BT about the issue with the SNR dropping when the phone is picked up and a chap called me back and didn't really seem to grasp why it was an issue. He just kept telling me BT are trialling dropping the SNR to 3dB and because mine was above that even with the drop caused by the phone, there should be no problem, ignoring the fact that the SNR shouldn't budge if the faceplate is doing its job properly.
Anyway, I'm going to take the faceplate off the socket later and run from the test socket with a filter to see if I get the same results; I suppose after all this it's possible I have a faulty faceplate. I still can't understand my sync dropping while the max attainable rose by so much but then I don't understand a lot about the problems I'm getting so there we go!
SNR still drops by 1.5dB up and about 1dB down when I pick up the phone, even when plugged directly into the test socket via an ADSL filter. That narrows out the filter in the faceplate being the cause and suggests either my phone or some equipment in BT land, unless anyone has any other explanation?
He just kept telling me BT are trialling dropping the SNR to 3dB and because mine was above that even with the drop caused by the phone, there should be no problem, ignoring the fact that the SNR shouldn't budge if the faceplate is doing its job properly. the 3dB noise margin relates to ADSL 2+ NOT Infinity if your noise margin is varying like that it suggests a line fault
So I'm still getting near daily resyncs, I've not swapped in the modem I've bought yet but I'm getting to the point where I'm going to have to just to try something else, but really I want to get to the bottom of the issues without changing yet another variable if I can.
BT acknowledged an issue which they claimed was a problem with a joint which should now be resolved, but I'm still getting desynched all the time and my stats still take a tumble whenever the phone is picked up:
Phone on hook:
Phone off hook:
The stats do slowly recover the longer the phone is kept off the hook but this isn't normal is it, I've seen the numbers go as low as 4.2/5.4 when testing? I've never had problems with the phone affecting SNR like this before, although I've also never had VDSL before I moved here.
Any ideas if something is still wrong or if this is just the way things are, and daily resyncs will happen whatever BT do?
The stats do slowly recover the longer the phone is kept off the hook but this isn't normal is it
That is symptomatic of a high-resistance fault. An engineer should be able to spot that.
Did you have an engineer come to your house at all?
I've had 5 engineers since install, but none since I reported the SNR drop on phone pickup, they said there was a problem with a joint and it would be fixed within 48 hours, which was over 48 hours ago now. I got a text the same evening I logged it saying fault cleared but obviously it isn't as I took the screenshots above just now.