Have you tried swapping the modems to see if it stays with the line or the modem?
I will try that at some point.
I'm going to ask about RJ11-RJ11 cables, do you use a UPS, get rid of microfilters and phones + extension wiring, the usual stuff...
Will you ask the A&A guys for their opinion?
I'm waiting for two RJ45 to RJ11 DSL cables (1 meter) to arrive in the mail, going to see if those help. Don't use an UPS currently. No microfilters or phones or extension wiring, I actually use printed DSL only face plates provided by A&A, as theres no PSTN service on these lines, only copper pair.
A&A know about the fault, and they know that I'm trouble shooting things my side first.
Those SNR dips on line 2 look a bit odd. Its almost reminiscent of what you'd see happening on the upstream if there's a HR fault.
Is there any telephony on that line. Can you do a Quiet Line Test?
No PSTN service on this line, only copper pair for VDSL. Quiet Line Test was clean, even got A&A to email me the mp3 of their recording and I looked at it in audacity, was clean visually too.
Also -> A&A's PSTN Test is OK, End to End VDSL Test is OK, BT Knowledge Base Connection Test is OK.