Update: Engineer has been, a different person but a very helpful person. He actually found a problem eventually but can't yet identify where or what the problem is.
He did the usual PQT test and such, nothing showed up as expected. He then did a lift and shift as requested on the job notes, no difference as expected. He then went out for a while to find me the best quality pair (now syncing at 75.3 / 18.2 at the moment, the highest sync so far I believe!), no difference to the errors as expected. Tester's modem showed minimal errors when not via the filtered faceplate as usual, then he tried plugging it in via the filtered faceplate and BANG! He had over 100 CRC errors per minute and they kept coming in
! He tried a different RJ11 cable, no difference. He then tried a spare filtered faceplate he had in the van, no difference. He tried a microfilter, no difference. He tried swapping the first line with the second line, no difference.
He's returning tomorrow morning again to check every point of the way (except the manhole on the main road since it's not easy to access due to traffic). If he can't find any problems elsewhere then he'll go ahead with requesting the 'manhole team' look into this I believe. The cable I'm going via is apparently 70+ years old, interesting to know. He suspects this is a slight high resistance problem or corrosion that's only noticeable when on FTTC, if I had ADSL I most likely wouldn't notice it. As it was when I was using the ASUS I tried restricting the D3 band tones and the excessive errors were almost gone. I can't tell you how glad I am that an engineer has now found the fault that I'm having! When I mentioned MJ Quinn did the first FTTC connection, well, lets just say he didn't speak highly about them
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