Noise Margin up and down

[Ham]

I am noticing big speed differences and noticed that my Noise Margin is changing a lot over past few weeks
when my noise is around 6 and i get around 3800/4000 kbps but when noise goes up to 14/16 it drops to as low as 1200 kbps

any advice ?

[Rik]

That's classic behaviour for a noisy line. How is the router connected to the phone line, eg extension lead, what else is connected to the line.

[Ham]

router is connected to the master socket nothing else plugged into it the connection used to be really good for past 2-3 years nothing has changed my end
i even tyred a differant router to make sure it was not a hardware fault and still the same

[Rik]

Do you have an NTE5 master socket, the type where the bottom part of the faceplate can be removed. What happens, if you do, if you connect there? What are your router stats, downstream noise margin, attenuation and sync speed immediately after a re-sync?

[Ham]

socket is an ADSL V1.0

stats up from earlier

Modem Status Connected
DownStream Connection Speed 3264 kbps
UpStream Connection Speed 448 kbps

ADSL Link Downstream Upstream
Connection Speed 3264 kbps 448 kbps
Line Attenuation 49 db 13.5 db
Noise Margin 9 db 24 db

[Rik]

The speed is low for the attenuation, even allowing for the increased target noise margin. I get 3000 on a 57db line. Have a word with support, they can test your line and, if necessary, get a BT engineer out. Be aware, though, that if he finds no fault, or a fault on your side of the master socket, it will cost around £160.

[Ham]

thanks for the help Rik i will poke support tomorrow and also do another couple of checks later

[Rik]

If your router is supported by Routerstats, that might help track down the issue.

[Sebby]

There's nothing obviously wrong, so unless a line fault shows up, I think it's going to be one for a BT engineer.