First post here...but I've been lurking a while trying to glean and understand as much as I can.
I have a copper connection of approx 4.5km to my nearest exchange (Wingham). I suppose I've had problems on and off for years, with periods of good service in between, but nothing as persistent as my current issue.
It started probably 3 months ago now, and was pretty consistent in that I would have a pretty stable connection during the day, then somewhere around 9pm, my connection would drop, and re-sync if I was lucky an unusable speed (and I mean unusable - 2Mbps here is a good speed!)
I raised the fault with TalkTalk (I've been with them since October last year), and went through the usual rigmarole of assuring them I have nothing connected to my master socket except a faceplate filter (BT) and a phone. After several profile changes on the line, an Openreach visit was arranged, but as I expected, as the visit was mid morning, everything was working and all line tests showed no problems at all. As our pole carries electricity too, he booked a cherry picker and returned in the afternoon to check and re-terminate the connection at the pole.
Things continued much the same - sometimes my router (HG633) would remain in sync for 2 or 3 days and speeds would remain usable, then the fault would recur - sometimes with the same pattern, sometimes totally unpredictably. The fault was raised again with TT, and the saga continued, with another OR visit (I was not present, but once again, the line was electrically perfect), and then last week a 3rd visit. The OR engineer was extremely helpful - this time the same line checks were carried out and passed. He then drove out to the nearest cabinet (2.8km away) and checked the terminations there, as well as stopping along the way as there was an earthing point shown on his diagrams which he said was something that was done in the 60s to phone lines, but is not good for broadband (PU point?). By this point I'd been scouring the web for similar problems and stumbled across REIN faults. The engineer suggested that I may very well have a RIEN fault with no prompting from me, but said he hadn't been trained fully although he had found and solved a few previously.
With nowhere else really to go with the fault at this point, I decided to try 2 other routers I had in the shed - a HH3, and and old Thompson 585v8 from Plusnet. To my surprise, both seemed to be far less susceptible to the fault than the TT unit. Mysteriously, the HH3 appeared to switch itself off after an hour or so (power saving not active either), so I continued using the 585.
I have been dabbling with routerstats, and it's new to me, so forgive me if I'm supplying the wrong info! I've been trying to monitor the downstream noise margin, but on the occasions when the fault occurs properly, it seems to freeze the program completely, so I'm unable to capture the resulting graph (maybe because I'm running under Linux and wine?), but on the occasions that I've witnessed it, the SNR margin remains stable at around 6db, then plummets momentarily before going up to 12db before stabilizing again. As well as this, I noticed large gaps in the bits/tone graph, but only ever in the Downstream portion (when the fault occurs and I run a speed test, it only ever affects the download speed, upload is always constant at around 0.7Mbps, when DL can be 0.1 or lower)
Pictures attached are of my current situation - not failed (obviously), but running about half normal speed.
I've tried the usual stuff with a MW radio, and not really found anything conclusive - I initially though my freeview box may be sending RF back up the mains, but the fault still seemed to occur with it switched off. Typically, since I found out how to use routerstats, the fault doesn't seem to have occurred to the point that I have no connection, but I will persevere.
Any help would be gratefully accepted!