Sync speed dropped from 23 meg to 6 meg

[#1]

There's been a lot of internal chatter some of which obviously makes no sense to me but I will repeat some snippets so you can see what you think.
First there was another one of those charts giving a visual indication of the disconnections which have reduced to almost zero by the looks of it but this was with the 15mbps sync speed.
This was followed by the letters KBD and then the results of what I assume to be a line test, I noted this part: maximum stable rate: 19296
The results showed the crica 15mbps sync and 12.5 SNR margin and 445kpbs upload sync (used to be around 1.2mbps I believe
Under the test results was this comment: "SFI found slight noise on line, so swapped d-side pair, line was still dropping sync so recommended a router replacement."
There was then some talk of setting the target SNR set back to 6 and then having to do it manually
The SNR is indeed now at 6 and these are the new router stats:

Connection Status Connected
Us Rate (Kbps) 439
Ds Rate (Kbps) 18905
US Margin 28
DS Margin 6
Trained Modulation ADSL2Plus
LOS Errors 0
DS Line Attenuation 3
US Line Attenuation 4
Peak Cell Rate 1035 cells per sec
CRC Rx Fast 2270
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path

Obviously well short of my previous near 24mbps.
I won't be able to a controlled reboot in the daytime until friday.
What is immediately obvious is that there are now errors occurring, I know for a fact this happened before my problems began and that some errors are normal but I don't know how many per an hour/day/week I was getting before so I have no way of knowing if the error count is in line with where it was before.
All I can say is that count has been reached in the past 4 hours and only in the last 20 minutes or so have I been home and using the internet so those errors were accumulated during very little traffic.
I have routerstats running and have started a graph for the error count. I will now do a mixture of streaming/usenet/youtube etc to simulate my everyday use and the conditions under which the disconnecting problem was at it's worse.

[#2]

This is a depressing comparison:
August:
<a href="http://www.speedtest.net/my-result/2902758182"><img src="http://www.speedtest.net/result/2902758182.png"></a>
Tonight:
<a href="http://www.speedtest.net/my-result/3171664344"><img src="http://www.speedtest.net/result/3171664344.png"></a>

[#3]

Looking at routerstats this morning it seems the error rate was pretty consistent and then suddenly picked up just a little while ago at 7am.
The noise graphs haven't budged all night.

[#4]

Error graph is interesting, but would be more useful plotted as "change since last sample" - right click the graph and tick the option.
Really do need. DCT view on this one.

[#5]

Ok I have set routerstats to plot difference between each sample now.
Looks like my profile has been reduced to 16.6 meg now, I'm not sure if this appropriate for my sync speed but I can tell you that speed tests and usenet now show about 1100kbps vs the 1400kbps I was getting last night when my profile was still at around 19meg

[#6]

Well my ticket got updated "your fault now appears to be resolved, the connection is stable at a good line speed"
I really don't think a speed test drop fom 2400kbps in August to 1400kbps is a good line speed 

[#7]

Sorry to dig up an old thread but my life has been pretty complicated (wife left etc) so my broadband become a low priority. My broadband did stop disconnecting and has been pretty solid ever since although my sync speed is still lower than it used to be with the 6db margin. I'm currently using a router that allows me to adjust the SNR and it's only when it's set to around 2.5 that I get the kind of speeds I used to although the connection appears to remain stable even when set so low. My exchange is only 100 meters or so away so that makes sense I suppose.
The main issue I am having now has been ongoing for several years, no matter what protocol or application I use my downloads seem to hit a fixed ceiling at around 1.7MB per second even though I should be getting closer to 2.4-2.5MB. No matter what program I use this happens. If for example I'm using usenet the download speed will shoot up to around 1.8MB then bounce back down to 1.7 and stay there relentlessly. I've taken my laptop to other people's houses and managed to get much faster speeds using the same computer, server, software etc it seems like some kind of throttling being put on my downloads. I made a thread about this a long time ago and we went through every kind of check imaginable but to no avail. Since then I have a new router, new computer etc but it makes no difference. Friends have bought their laptops and tablets around and experienced the same thing it's like hitting a brick wall.
Occasionally if repeatedly connect and disconnected I will suddenly be able to download at full speed usually around 2.4-2.5MB but after a few minutes the speed will suddenly plummet back down to 1.7 I find it very exasperating, I have the good fortune to be close to the exchange but my download speeds are slower than friends who live much further away!
The only thing that stands out to me is that years ago I had a slower router and my snr was set higher and my router would connect at about 14meg and give you guessed it, 1.7MB downloads. Ever since I got a fast router and originally requested my snr to be changed to 6 my download speeds have stayed the same even though my sync speed went from 14meg to 22+ I don't know what the means though!?
I've also noticed that since I had disconnecting problems my upload connection speed has gone back down to 448kbps.

[#8]

Hi fatdeeman,
I've taken a look through your line stats and all the profiles seems to be aligned so there aren't an problems that immediately jump out at me. Would it be possible for you to provide a speed test from here via a wired connection directly to the router. Once the test returns the speeds if you could hit the 'Further Diagnostics' button as well and post the results we can start to take a look into this for you.

[#9]

Here's the speed test

[#10]

For comparison this was August last year but I was still getting 1700KBPS usenet even when I was getting these kind of results.

[#11]

Is it possible that the capped upstream isn't fast enough to send acknowledgements and requests for more data at a fast enough rate to allow downloading at full speed? I think it's unlikely because the acknowledgement packets are so small. But it might be worth checking the upload speed being used while trying to download at full speed, or when the download part of the speedtest is running. Windows Task Manager is just about adequate for that, you can add a bytes/interval column to the network utilisation data.

[#12]

I've decided I want to upgrade to fibre so hopefully this issue will become irrelevant.
Does there have to be an engineer for that or can you do a self install? Any special deals for loyal customers of ten years!!?

[#13]

Quote from: fatdeeman

Any special deals for loyal customers of ten years!!?

What do you think Plusnet is....a bank? 

[#14]

Hi again fatdeeman,
Give our Customer Options team a call and see what they can do for you, I'm sure there will be a deal to be had    - 0800 013 2632