Sudden drop in Noise margin: cause?

[Culinia]

Why did my connection drop (for no apparant reason)?

I was wondering if some of you could help me with this problem I've been having recently: connection dropped for no reason. Now I know my line is not the strongest lines but what causes such things? It was healthy at 10db before dropping suddenly down to 0 without any reason?



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This is my 'line stats' now as posted from my router (Netgear DG834GT)

ADSL Link Downstream Upstream
Connection Speed 2112 kbps 448 kbps
Line Attenuation 63.0 db 31.5 db
Noise Margin 9.0 db 16.0 db

And here are the logs when it happened:

Mon 11 Jul 2011 19:02:38, Noise Margin= 9.8, Sync Speed= 2144
Mon 11 Jul 2011 19:02:53, Noise Margin= 9.9, Sync Speed= 2144
Mon 11 Jul 2011 19:03:08, Noise Margin= 9.8, Sync Speed= 2144
Mon 11 Jul 2011 19:03:23, Noise Margin= 9.9, Sync Speed= 2144
Mon 11 Jul 2011 19:03:38, Noise Margin= 9.4, Sync Speed= 2144
Mon 11 Jul 2011 19:03:53, Noise Margin= , Sync Speed= 0
Mon 11 Jul 2011 19:04:08, Noise Margin= 10.1, Sync Speed= 1440
Mon 11 Jul 2011 19:04:23, Noise Margin= 10.1, Sync Speed= 1440
Mon 11 Jul 2011 19:04:38, Noise Margin= 10.0, Sync Speed= 1440
Mon 11 Jul 2011 19:04:53, Noise Margin= 10.2, Sync Speed= 1440
Mon 11 Jul 2011 19:05:08, Noise Margin= 10.2, Sync Speed= 1440

Mon 11 Jul 2011 23:38:21, Noise Margin= 9.0, Sync Speed= 2112

When I came back to the computer I rebooted and resynced it from DMT Tool. In this case and before the target SNR was at 110% thinking that this would prevent future outages but obviously this has not helped.

Could anyone help me? Thanks.

 

[dmsims]

Routerstats (full version) works with your router and will give you a much better picture. It's impossible to say why the line dropped - a spike in "hard" errors from interference, maintenance.

Get the full version running and let's have a look at the detail

 

[Skidilliplop]

noise margin dropping to 0 usually means the router got physically disconnected from the line or the line shorted.
Could be a BT engineer with fat fingers or a wild scredriver. Or it could be your dog trod on your modem cable. Given it only lasted a minute period I wouldn't lose sleep over it.