Changes over months: getting worse. Info?

[#1]

I'm wondering the best way to start on a problem of falling downoad speeds, associated with apparent changes to the service over several months. The history is suspicious. After a couple of months of relatively reliable service with line speeds of 5696, 5632 and then 7168K, we had an automatic new line 8 times during June with line speeds between 6304 and 7616 (plus one short spell at 704 immediately following a power cut). The line only automatically renewed twice over a five-week period in July, again with good speeds. Since 30 June, it has all gone wrong. The automatic new line on 30 June had a speed of 448K. After I switched the router off and on a couple of times, the line came back at precisely 6400K, but with dismal download speeds. Since then I have again switched the router off and on twice (spaced out: on 30 June and 2 July). On both occasions, the line speed has come back at precisely 6400K. (I have never known the speed come back at the same value three times in succession before.) Meanwhile the service does not match the line speed. Since 30 June, ping times to various servers have varied randomly between 15millisecs and over 5 seconds, and download speeds have varied between 120 and 520K. Today - even worse. I can clearly see, as I use the internet, that the downloading is coming is widely spaced quick bursts. All this suggests to me that there is a congestion problem somewhere upstream. I have looked up service status and the info on my exchange many times, and see nothing. Can Plusnet please just check whether you think my service (via the Netherend exchange) is being provided OK before I waste lots of time (as I have done in the past more than once) repeating all the checks for my end yet again? (While we're at it, is it possible to get more info on what is actually happening generally. Conversations with engineers suggest they are well aware of problems when neither BT nor Plusnet admit to anything.)

[#2]

UPDATE AND CORRECTION
1. Apologies. From the "Since 30 June" in my post, all the dates I mentioned were one month behind. A mental lapse, I'm afraid.
2. As I finished posting, the download speed slipped to 100k. In despair, I switched off the router again. On switching on, my line speed is changed and download speed is about 5.5M. Thank you.
(I still wonder what goes on.)

[#3]

Hi,
What do you mean by an automatic new line?  In correct terminology can confuse people.  Do you mean a new PP session (a change in IP address)?
I recommend that you take a look at the speed issues thread - see link below - and then post the requested information.
Do a quite line test.  Check out your internal wiring.

[#4]

Sorry Townman. No, I do not mean PP session. When I said line, I was talking of the ADSL connection between my router and the exchange (that is sometimes referred to as having a "line speed"). What I meant by "automatic new line" was that the ADSL connection was terminated and then restarted without anything being initiated at my end. More information on how and why that happens is just the kind of thing I would like to know. On my understanding, the PP session is not a primary issue. The two primary issues appear to be: 1 ADSL and 2 the service delivered when the PP session is in place. Whether there is any linkage between these is, again, something I would like to know. (I have previously been through the works of checking and changing my internal wiring, getting BT to replace their dodgy connection at the nearest pole, etc. The setup at my end is the same as when I had ADSL line speed over 7M for a couple of months earlier in the year. And one advantage of an isolated location is that there is no source of interference nearby.)
Meanwhile, things are deteriorating again. The 6432K ADSL connection (with download speeds around 5500K), that came just after I posted to this forum previously, didn't last. On Saturday 8 August, there was a period when the line/whatever between my router and the exchange was completely dead. The same happened again on the morning of Sunday 9th. There was a couple of hours of further instability in the middle of 10th.
As of lunchtime on 10th my ADSL is good, with line speed is 6432. However, what comes over it is back to the stuttering that was occurring before I started this thread. Ping to test servers varies from 265 to 3636ms. Downloading is clearly in sudden bursts of good speed between poor speeds. Effective download speed varies from 0 to 1M, but was mostly between 300K and 500K, until it dropped to between 100 and 150K this morning.

[#5]

Hi Woodsider,
Lets see if we can clear up terminology and your understanding.
The line is the physical copper wire between your home and the exchange.
The xDSL session is the "synchronisation" connection between your router and the exchange - you might consider it to be an ADSL 'dial-tone' - no xDSL synchronisation = no means of requesting a connection to the ISP - it is this connection which governs the synch speed, nothing else
The PPP session is a logical connection between your router and your ISP - it is this connection which allocates your internet (IP) address - when this breaks / drops you get a new IP address unless you have requested (and paid for) a static IP address
Problems on the physical line can lead to a loss of synchronisation which will lead to a loss of PPP session.  Hence being clear in what you mean (think is happening) is very important.
Data speed is influenced by a number of factors, starting off with how the PC is connected to the router and how error free is your line, followed by the IP profiles (BTw and PlusNet) being set correct for the current synch speed and the capacity of the BT exchange to transfer data to / from the ISP.  All of those factors need to be investigated to identify what might need to be fixed.
You might well have had your line et al checked out in the past - things deteriorate - BTOR do work in cable junction locations for other subscribers and could have disturbed your circuit (line).  It is therefore imperative that you follow the process (even if you've been through it before) with your current issue.

Quote from: woodsider

I'm wondering the best way to start on a problem of falling downoad speeds, associated with apparent changes to the service over several months.

Please read the speed issues thread and post all of the information requested there - speed figures alone are not enough for the community to help you.  Thereafter, raise a fault report using the link below.
Have you done the quiet line test?

Quote from: woodsider

And one advantage of an isolated location is that there is no source of interference nearby

...is no reassurance whatsoever - in the majority of cases of interference being the issue, it is from within the user's own home - it is simply a matter that they have no idea that it is there until the look hard for it.  I have been there myself!  

[#6]

Unfortunately as you are on a 20CN service any changes in the sync speed (5696, 5632 and then 7168K) can take up to 72 hours to reflect in the profile changing, and therefore can take that period before you see any improvement in speed test results.
At the moment your line is in sync at 6432, giving you a profile of 5500 and has been connected without drops for nearly 48 hours.
The instability you mention can be seen on the graph below too:

[#7]

That's interesting Chris. I concur.
So is this from BTW:
"Download speedachieved during the test was - 0.36 Mbps
For your connection, the acceptable range of speeds is 0.05 Mbps-0.5 Mbps.
Additional Information:
Your DSL Connection Rate :6.43 Mbps(DOWN-STREAM), 0.45 Mbps(UP-STREAM)
IP Profile for your line is - 0.35 Mbps"
How is the speed achieved higher than the IP Profile?
If the IP Profile is 0.35 and the "acceptable range" is up to 0.5, how did I get downloads earlier today at 0.70?
As I have been at 6432 since Monday lunchtime, and got up to 1.0 then, has my IP Pofile just been lowered almost two days later, or did I get 1.0 on an IP Profile of 0.35?
Thanks Townman for reminding me of the definitions. As I was getting download speeds of 5.5Mbps from last Thursday to Saturday on the same sync speed as now (after startng this thread), there is not that much that can have happened to reduce my home capability to one tenth. On the other hand, while I use almost all my home electrics overnight and the "xDSL sync" stays stable, Chris confirms that all the interruptions have been during the day.

[#8]

Update 16.30.  BTW again gives my download (0.37) speed as faster than the IP Profile (0.35).
Chris: You say that my line is in sync at 6432, giving a profile of 5500. Is that profile figure an "ought to be", or do you actually read that 5500 somewhere, contrary to the figure that BTW gives me?

[#9]

Ah sorry, that *should* be a profile of 5500. Although as it's such a large increase in profile it shouldn't take more than 24 hours for it to increase. If it's not increased by the morning then give me a nudge and I'll do a line reset to give things a kick.

[#10]

BTW is still giving my IP Profile as 0.35Mbps. That's after 67 hours synced at 6432Kbps.
I also note that Ping is around 39msec since shortly after you posted, Chris. Over the previous days it had been anything from 200 to 3636msec. I don't know whether I should be thanking someone, or whether this is evidence that things more fluid that IP Profiles and sync speeds are now improving.

[#11]

I've just reset the line which should sort out the profile issue, resets should happen near straight away but can take a few hours. Let us know what the profile shows next time you do a BT Speedtest.

[#12]

Thanks Chris. Instant! I'm now downloading at over 5Mbps while my wife is browsing on another machine. I'll do a test later when there is no other usage.

[#13]

Now:
"Download speed achieved during the test was - 5.51 Mbps
For your connection, the acceptable range of speeds is 0.6 Mbps-7.15 Mbps.
Additional Information:
Your DSL Connection Rate :7.62 Mbps(DOWN-STREAM), 0.45 Mbps(UP-STREAM)
IP Profile for your line is - 6.5 Mbps"
Thank you.

[#14]

Excellent, much much better!

[#15]

Chris.
Yes, indeed! It has often been as good as this during the last couple of years. Such a shame when it does fail after all from time to time.
Townman.
Apologies that the thread title was possibly misleading. Had my broadband deteriorated gradually over the months, your response would have been appropriate. But it didn't. It has been good this year (excepting periods of power cuts) except for:
22 March to 3 April (pre-Easter). Several resyncs, unexplained.
5 April to 11 April (Easter week). Appalling, with several periods not synced at all.
3 June to 11 June. Appalling, but partly due to power cuts.
30 July to 13 August. Various: Periods not synced. Download speeds switching from fast to standstill minute by minute and hour by hour. Plus low IP Profile problems.
I could ask this year, as I did in a thread a few years ago, why everything goes pearshaped during school holidays, but I have learnt better than to expect a response.
I have asked this time, as PlusNet have always told me it cannot happen, how come my download speed is faster than my IP Profile according to BTW? As yet, no-one has given any response.
I have previously asked how it can be that engineers can give people good advice about work in their area, and nothing is forthcoming from BTW and PlusNet.
I am hoping you can see why a plea for "Info" was also tagged onto the title.
By the way, I am sure you are absolutely correct that "in the majority of cases of interference being the issue, it is from within the user's own home". There is however a limit to how many times people can take this tamely, when previous form suggests otherwise in their individual cases. Sorry if my annoyance came through inappropriately.