Yet another 'Happy Customer' with plummeting Linespeeds (Thanks Openreach)
Apologies for being very 'Brassed off', so this will be blunt but 100% truthful.
In total exasperation I am going to ask for help from Plusnet.
I have had my line since 22/08/2014 (round figures 18 Months)
I had a good 80/20 line that after 1 line fault + 1 DSLAM Fault and 2 Openreach Engineer visits (making the line worse) ended up capped at 66999 since well before Christmas.
[That 66999 figure is a common 'Capped' figure that people report, too precise and repeated to be a natural limit, I think!!]
I lived with that after the last attempt to get Openreach's crappy performance rectified by Plusnet and the total Zero response I got to that!!!
Now I am getting 60000/20000 on a line that has a Max attainable of 716xxx (min) 719xxx (max).
[For the last 11 days 10 hours 42 min 1 sec solid, as I write this.]
As per below I had a line resync and I dropped from 66999/20000 to -->
A resync/restart occurred on your line at 31-03-2016 13:20 local time (+/- 1 minute). Reason: 1 Remote Defect Indicator/DLM Current Downstream Sync Rate is now 60000kbps Current Upstream Sync Rate is now 20000kbps
I have waited to avoid the standard response to wait and see if it improves ---- IT HAS NOT!!!
I am on a line that terminates at a chamber at the foot of my drive and supports ONLY 5 Max other lines.
[I have pictures of the lines that terminate there from last Openreach visit --- SO NOT CONGESTION!!!]
My drive is max 3 carlengths long and the line terminates at my house on the same side as the Drive.
My Line should be able to support 80/20, it did quite well before it was screwed up by Openreach.!!!
My original Line Estimate was: (From the Plusnet email after 14 days of line usage)
Estimated line speed: 2Mbps Current line speed: 77.4Mbps
I got 80/20 with no problems (until the 1st & only line fault)
Now there is NO estimate on file on the Plusnet Page and I get 55.4Mb as my speed.
My BT Line Test is:
Conveniently the acceptable range for my line is now 40-55.58Mb which just so 'fits' around my new lower speed.
It changes to 'Track' the drop as it did when the line was capped at 66999 after the Openreach engineer made my line worse and left it to 'improve'. (Which it did not!!!)
Finally, the question, could Plusnet get Openreach to fix my line without making it worse back to at least 66999/20000. (My sights are low as I expect little.!!!)
Thanks for your attention and patience reading this.
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Addendum: Other Stats
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Ray,
Thanks for the response, I would possibly agree but past experience has shown that what I think does not matter 
Plusnet and Openreach need to agree that there is a fault while BTO's tests tell me the line is fine ..... just slower for no known reason.
The drop to 60000 from 66999 was 1 DLM resync and not a gradual line degradation which you might expect with Contention and/or increase in line interference.
I monitor my line 24/7 using DSLstats (wonderful useful proggie via kitz.co.uk ) and can see the instant drop.
Cheeky Advert for Kitz from Happy Member (Really!!) :
Visit kitz.co.uk and you will get all the information you will ever need to understand/monitor your line with DSLstats and other wonderful software by some of the very helpful people who 'live' there.
Very Techie clever people ("You know who you are!") who are happy to help the 'Dumb Users' out there, without treating you like something they 'trod in'
Lots of support and 'Good Information/discussion' from a very friendly group ... say Hello to Kitz for me.
[I will get a 'Slap' from Kitz for doing this <Ducks and runs!!> ......]
P.S. Moderator, I will not do this again. Thought it was worth a mention to help people understand their line and avoid the repeated questions that get posted and Plusnet deal with over & over. Just trying to help.
Andrue,
Quick reply, I did not say DSLAM.
I cannot remember the correct terminology for the chamber.
It is where the lines from the DSLAM are accessible to BTO to install new connections to houses on this part of the street. There are other similar chambers at other parts of the street (My end of the street is a Cul de Sac with approx 10 houses.)
i.e. to give someone a new or extra line or to enable a pair swap to be made.
There are only 5 lines that are connected to houses, from that chamber, and a huge cloud/tangle of unconnected lines that are available for use in the future.
I took photos when the last Engineer came.
When I was moved to a new pair, I was connected to one of the 'unconnected' lines.
(Obviously they are connected at the other end but language/terminology can be a problem )
I drive over the Concrete cover every day as I park on my drive and NO work could be done without me knowing as I could not get on/off my drive without Driving over it.
Not to mention a BTO Van would be obvious on the end of my drive
Hope that is clearer, if you know the correct terminolgy please let me know and I will try to remember it in future.
The drop to 60000 from 66999 was 1 DLM resync and not a gradual line degradation which you might expect with Contention and/or increase in line interference.
Well contention doesn't affect sync speed anyway so that's certainly not the cause. I still don't see any reason to rule out crosstalk. A 13Mb/s drop (assuming you meant 80000, not 60000) overnight doesn't change anything. DLM is designed to improve stability. Part of that is going to mean that it doesn't keep resyncing your line at the slightest provocation. It may well have hung on for a couple of weeks tolerating increasing error counts before it finally threw in the towel and dropped you. Do your graphs show error counts? I'd be a bit more sceptical about crosstalk as the cause if you could show no changes there until the DLM drop.
It wouldn't rule it out entirely though. Crosstalk doesn't steadily increase. It's more like being stood near the target on a firing range with people firing shotguns. The more shotguns being fired the greater the risk of you being hit. But you might escape unscathed. Or perhaps the first person to fire catches you full blast. It's just pot luck.
I know you'd like to think this can be fixed and by all means try and raise a fault but I think you need to prepare yourself to accept that it's just crosstalk. The sooner you do that the sooner you can calm down and take a more relaxed approach to the issue. People at PN and BT may be more prepared to work with you on this if you can remain polite and friendly toward them. It is after all highly unlikely that they are deliberately trying to muck you about. Most of them want to help you but it can be difficult to make the effort if the customer is antagonistic.
Edit: Seen your reply about the chamber. I'm not sure what they are called either but for the purposes of this discussion it's irrelevant anyway. Congestion is when there is more data trying to flow down a network branch than the branch can handle. It's a purely digital phenomena and has nothing to do with physical cabling. The only thing the contents of that chamber could tell you is whether or not the cable connections are electrically sound.
They are a possible location of faults (mine once got flooded which took out my phone but left the ADSL unaffected) but that's all. There is a possible link between the number of cables inside that chamber and crosstalk but without extensive diagnostics we can't say more. In any case unless you can persuade your neighbours to forego broadband there's nowt you can do if that's where some of the crosstalk is occurring. And crosstalk can occur anywhere along your cable so the chamber may or may not be relevant. The nice thing about FTTC (unlike cable) is that your telephone line cannot by definition be congested because you're the only one using it. Congestion can only occur where the lines merge and that is at the cabinet (for FTTC) and the exchange (both FTTC and ADSL) and deeper into the network. It's a lot like a road system. The closer your car is to your front door the less congestion it experiences and it never gets congested on your driveway
Basically that chamber is just a hole in the ground that your cable passes through and can be ignored.
It may well have hung on for a couple of weeks tolerating increasing error counts before it finally threw in the towel and dropped you.
Nope, not true have stats to prove it.
A 13Mb/s drop (assuming you meant 80000, not 60000) overnight doesn't change anything
Nope, I meant 60000. I don't understand your point with 80000 vs 60000. I am quoting figures from my stats and I am NOT ignoring the fact that I was capped on 66999 prior to the DLM resync.
... antagonistic
Your view on antagonistic does not match my understanding of the word but I don't want to debate semantics.
At the end of the day, from past experience your view or my view does not count regarding this issue.
You are free to debate it but I would rather see what Plusnet and Openreach think, as they are just as likely to NOT care what you say/think as they I.
I have had these 'Discussions' before and at the end they are of no value other than to waste time/energy and generate a lot of stress.
Thank you for your input but lets see what Plusnet/Openreach can do, rather than debate round in circles.
Finally, I do understand how DSL works, even if you may not agree.
(30+ years of working with Computers/Comms, so sort of get the idea even if I am not a BTO Engineer. )
I am simply not able to think of the correct terminology/words due to chronic illness, for which I apologise.
Again, thank you for your input.
The thing is that I have just had almost the same experience where my line was capped to 60000 but I put it down to the engineer doing it as he arrived at the same moment as the cap. I just had another engineer visit who reset the DLM so the cap has now gone.
Sorry to hear you are ill btw. get well soon 
Ray,
Thanks for the concern, but not likely to get better too soon 
Re: Line Cap, it is what it looks like but it is a 'pain' convincing Openreach to do a DLM Reset without a 'real' fault as far as they are concerned.
Unless Plusnet can now request DLM Resets directly without a BTO Engineer visit , which is not likely as far as I know.
The annoying thing is that you can see periodically DLM make 'decisions' which are based on a transient event that 'locks in' a line rate or G.INP setting etc etc
DLM then does not 'adapt' after the event but stays in that 'Locked' mode.
That is what usually is cleared by a DLM Reset but ....... back to original problem of 'No Fault' therefore 'No Reset'.
FYI
I had a number of total power losses due to some clever man with a digger knocking out the power for 20000+ people and the subsequent 'bouncing' of the power supply when fixed/refixed etc
This happened in the weeks(???) before the DLM resync and I think that DLM eventually decided to bounce the line.
This also was when I found I could not get a new PPP session when the router restarted.
(There is a facility to close/open a new PPP session on my router if it does not re-establish BUT it would not work and I ended up leaving the router synced as far as DSL was concerned but unable to get a PPP session and therefore had NO Internet access for most of the day.)
Eventually, I had to restart the router (Full Power off) 2-3 times until sometime after 00:00 hours it synced again and the PPP session established.
All 'grist for the mill' for DLM as we all know.!!!
Side Question:
With the new forum do I need to log a fault call as well or will this problem be picked up from the forum ?
I do not use Plusnet for support unless pushed, so do not know if things have changed since my last fault.
Thanks for your help.