Massive drop in line speed...

Question

Hi all,
I suffered a massive drop in Internet connection speed earlier this week which has so far not improved.
Although I have had ADSL since it's near earliest days and being close to my exchange I have never received a great performance but have become more or less satisfied with the 4\4.5mbps I receive from my Total Broadband Option3 package.
I did receive close to that speed prior to the 8mb upgrade a few years back and an upgrade to 20mbps doesn't promise me any better (availability checker for neighbours etc suggests that faster is available but who is to know?).
On Wednesday (9th February) my connection\synch speed dropped to about half it's usual speed and is now in the region of 240kb rather than the near 500kb I usually receive. I would like to comment that I know my line can achieve better than this as I got download speeds of nearer 600kb for a month or so around October last year.
I power-cycled the router and after the diagnostics had completed etc and the line synch process had  completed the speed of the line had dropped again slightly.
Not to sound arrogant but I know all the usual troubleshooting having been through it all before on several occasions each time finding out the issue is with the exchange and so having had no means to affect the problem.
The situation is the same this time in that categorically nothing has changed inside my home nor with my equipment and so I am confident that the problem is external to me, especially considering the massive drop in speed.
I did get a response from a BT forum moderator from a post I placed on another site but the advise I got back was generic at best and didn't suggest anything besides mounting a BT iPlate. that advice was no good for two reasons which are that as nothing in my home has changed fitting an iPlate won't make a 2+mbps connection increase (back to what it was) and that I already have an 'ADSL v1.0' labelled master socket that already contains all the tech that the iPlate does. Having replied to their email stating that I already have the afore mentioned v1.0 master socket I haven't had any response.
So... to explain further...
here are some diagnostic stats for the past couple of days taken from my router (Draytek Vigor 2820n) - sorry the font is small bu tI wanted to keep the layout of the text when I completed the post;
> ADSL status @ 04:43 10/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2528000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2592000 bps   US Attainable Rate   :  1100000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       15  dB
   DS actual PSD           :    18. 6 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 09:33 12/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2976000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  3328000 bps   US Attainable Rate   :  1104000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       16  dB
   DS actual PSD           :    19. 3 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 04:07 13/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2880000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2912000 bps   US Attainable Rate   :  1100000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       15  dB
   DS actual PSD           :    18. 7 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
The BT Speed Tester web-site reports my line speed as 2mbps when it was previously 4.5mbps and so as to check actual download speed independently I ran a comparison speed test via SpeedTest.Net which reported much the same result (down\up speed relative to what you would expect for a 2mbps line - Link to SpeedTest.Net results: http://www.speedtest.net/result/711802566.png ).
As you can see from the diagnostic data, the SNR is high and so it does seem to suggest that there is fault on the line. prior to the fault, the SNR was around 6db rather than the 15\16db reported now.
I know it has little factual baring on this incident's potential problems but my last broadband speed issue was caused by water having gotten into the top of the telephone pole at the end of my street which was temporarily fixed by a BT engineer but I don't know whether that was ever permanently fixed?
During that occasion I did suffer very slight noise on my telephone line which I must say isn't the case this time but I thought I would request a line test once again in any case. That unfortunately hasn't helped as the online system tells me 'telephone number not found' and so I can't proceed with the test.
Can anyone offer any advice or is any BT person willing to take on the issue and see it to resolution for me please?
Even trying my own diagnostics trying to speed things along by obtaining a line test hasn't been possible.
I do appreciate that there is a support system in place but that has failed me on this occasion and so I have no faith in going throught the telephone support for BT Broadband when I know that nothing I can affect is at fault.
I can of course provide my account details, email address etc. to anyone BT techie that can assist and I am happy to run any further diagnostics that might me appropriate under the circumstances.
Thanks in advance for any advice and\or furtherance anyone can make towards resolving my issue.
Regards,
Dizzy
PS> if my speed increases beyond 4.5mbps I won't be upset!

Answer 1

5 days into the problem and nothing much has improved. My line speed has now sync'ed into the realms of 2.5mbps so I am at least seeing circa 300kb download speeds (but that's still at least 50% less that I had).
At the end of this post are the latest batch of diag results for anyone who wants to check them over. The only details that seem to change are the 'Cur SNR Margin' and as a result he downstream actual\attainable rate(s).
It just simply seems that something has screwed-up the line and now I'm going throught the tedious increase period to get back to where I was. As increases always take longer that decreases it could be some time before things get back to normal (if they are on a slow increase that it!).
The Kitz Site has some good information related to BRAS profile increases\decreases and depending on how small the increases (if any) are coming my way it could take a very long time to get back to 4.5mbps or thereabouts.
At current rates if increases continue it could be at least 15 days (at 1/2 mbps per 5 days) making it some 20 days total to get back to where I was. All because of a fault that lasted a a fraction of a second.
It is worth mentioning that I did have a similar long period to wait for my line sync speed to increase as a result of the water having gotten into the top of the telephone pole some time ago, which I mentioned in an earlier post, but at that time the drop wasn't too big and so a few days saw the previous performance restored.
For the benefit of others that may read this post, I've explained in my email message to Stephanie that, I have checked with neighbours for any changes they may have made electrically, which they say they haven't, and confirmed that my modem is connected directly to the master socket, and that the master socket is an NTE5 socket so I don't need an iPlate.
I also mentioned that I have ferrite RF chokes on the extension lines and the router<->ADSL line (supplied with the router itself) to cut RF interference that may be picked up by the system.
On a related note, it was commented in another thread that RF chokes can cause problems with ADSL comms but that is not true (I've done a heap of research on the subject). That being said, they can actually have no effect at all if not installed correctly which is why the snap-on-cable type is best because you simply can't get it wrong.
Anyhow, here are the stats and I hope things continue to improve, even if it does take 20 days!
> adsl status @ 12:44 13/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2880000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2912000 bps   US Attainable Rate   :  1100000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       16  dB
   DS actual PSD           :    18. 7 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 17:56 13/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2944000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2976000 bps   US Attainable Rate   :  1108000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       15  dB
   DS actual PSD           :    18. 9 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 04:30 14/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2944000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2976000 bps   US Attainable Rate   :  1108000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       12  dB
   DS actual PSD           :    18. 9 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 21:29 14/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2944000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2976000 bps   US Attainable Rate   :  1108000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       14  dB
   DS actual PSD           :    18. 9 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 03:19 15/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  2944000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  2976000 bps   US Attainable Rate   :  1108000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       12  dB
   DS actual PSD           :    18. 9 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >
> adsl status @ 11:03 15/02/2010
  --------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            :    G.DMT       State                : SHOWTIME
   DS Actual Rate          :  3008000 bps   US Actual Rate       :   448000 bps
   DS Attainable Rate      :  3040000 bps   US Attainable Rate   :  1100000 bps
   DS Path Mode            :  Interleave    US Path Mode         :  Interleave
   DS Interleave Depth     :       32       US Interleave Depth  :        8
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :       15  dB
   DS actual PSD           :    19. 1 dB    US actual PSD        :    11. 9  dB
   ADSL Firmware Version   : 232201_A
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       31 dB    Far SNR Margin       :       19  dB
   CO ITU Version[0]       : 0000414c       CO ITU Version[1]    : 00004342
   DSLAM CHIPSET VENDOR    : < ALA >