Kafkaesque Problems with Plusnet Support - Speed drops 60% at night

[#1]

Have just monitored the connection (using chrome and chrome canary browser) between 8.30pm -11.20pm and uploaded a series of speedtests to BTW site.
Still a big drop off tonight about 60% from the high 12 to 13mb download speed i've been getting throughout the day though slightly better than last night when speed dropped to 3.5mb. Download pretty much held around 5MB during bad period this evening.
Speed started to drop about 8.30pm and continued to drop reaching low of 4.98MB at just past 10.30pm. Again what i find really odd at 11.20pm speed had gone up to 9.7mb and i assume will climb higher and be fine during the day tomorrow.
Has anyone seen anything like this before? Does anyone have a list of possible causes? `most likely causes? Or does it not work like that?

[#2]

Also got a ticket update today support say again line is fine.
Confirmed that their testing on Saturday caused the drop in download speed from 14.6 to 7MB.

[#3]

The line is probably fine - it sounds like exchange contention.

[#4]

+1  for that opinion!

[#5]

I'm getting this looked into although it is showing as ok.

[#6]

Did you mean congestion?
If so is there anything that can be done about that? I'd expect perhaps a bit of slowdown in the evening but not losing 60 odd percent of the speed.
If it is congestion is this a plusnet problem or a general infrastructure problem? Ie would moving to another provider fix the issue.
Again today as of now speed is fine download around 13 MB or just under.
10.30pm or just around seems to be the low point i'll hopefully have chance to upload another test at this time tonight to BTW.

[#7]

i know Chris, it's really weird.
Line seems totally fine. No drop outs or slow downs during the day. Only at that evening time period.
You mentioned previously the exchange is not over capacity? Can you pull the network traffic figures to the LORDS exchange during the peak evening hours 8.30pm-11pm? Could this rule in or out a congestion problem?
It was actually not as bad last night. Rather than 3.5MB download speed the line was pretty steady around 5MB - Still a big drop from 13MB in the day. Could this variable nature indicate something like congestion? or any other possibilities?
Thanks for the help so far

[#8]

Same issue again last night speed fine all day 12 -13MB download.
At 10.30pm this had dropped to 6MB.
This week it's been worst on Tuesday evening when it dropped to 3.5MB around 10.30pm. Only thing i can think was different was England were playing. Does this perhaps indicate some form of congestion or server overload?
Plusnet have stressed that from their tests nothing is wrong with the line and as i've said it appears stable and true to the line speed at all times apart from the 3 hour window mentioned.
A couple of things I'd like to ask. Alongside BTW website i've been using speedtest.net to track download speeds. Firstly, does speedtest.net have a good reputation for accurate results? Secondly, if it does what i have noticed is during the worst moments around 10.30pm the speed indicator graphic seems to hit some sort of invisible wall around 4-6mb and go into reverse. Is this just an inaccurate graphical representation of what's happening or a true reflexion?

[#9]

I'd suggest also using the thinkbroadband speed test as corroboration.

[#10]

AAISP monitor exchange congestion (using their own parameters/methods) and publish it now: http://clueless.aa.net.uk/congestion.cgi
BT do not publicly publish their spreadsheet showing exchange congestion problems for the 21CN network.

[#11]

That's really interesting about the congestion.
Is this not something that Plusnet could be looking at (at least privately) to see if that could be at the root of the issue?
Here is the speedtest from thinkbroadband attached below. Oddly it seems slower than speedtest.net ones?
I will try to upload a comparison speed tonight at 10.30pm using the thinkbroadband tool

[#12]

The thinkbroadband test is generally more realsitic of real speeds testing both single multiple threads.
I don't think you answered this:

Quote from: jelv

Sorry if I've missed it but are you connected to the router wired or wireless?

[#13]

Sorry missed that question.
I generally use wifi in the day. The speed i just posted was with wifi.
But since the issues have arisen this month I've done the testing on a wired connection.
At first I thought it may have been wifi issue but with a wired connection the problems between 8.30pm-10.30pm still persisted unfortunately.

[#14]

I'd be interested in seeing if a wired tbb speed test showed the same variability as the one you've posted.

[#15]

Just tried to do that but my plugable ethernet to usb adaptor doesn't seem to be working.
I'll try to get another one tomorrow and then post results.
From the previous upload does my wifi connection seem particularly flakey? Router stats always say interference is acceptable?
thanks for the help.