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Drops and absurdly low downstream SNR

Posts: 78
Thanks: 1
Registered: ‎26-01-2011

Drops and absurdly low downstream SNR

After being very stable since the backend upgrade last August, my connection has dropped several times in the last 24 hours. Current stats are:

Modulation : ADSL2+
Annex Mode : Annex A/L
Line State : up
Lan Tx : 300893150
Lan Rx : 199546096
ADSL Tx : 910
ADSL Rx : 872
CRC Down : 0
CRC Up : 607
FEC Down : 0
FEC Up : 865
HEC Down : 717
HEC Up : 0
SNR Up : 7.1
SNR Down : 0.3
Line Attenuation Up : 11.8
Line Attenuation Down : 20.0
Data Rate Up : 1048
Data Rate Down : 18094


That SNR Down doesn't look right -- has the interleaving come off again? And if so, can someone please put it back? The speed is nice, but the drops are getting annoying. The line usually seems to be happiest with SNR Down around 6.


(It's losing sync as well as internet connection, usually coming back on its own within a few minutes so far, but I've been here before and it tends to get worse before it gets better.)

Plusnet Staff
Plusnet Staff
Posts: 34
Thanks: 8
Fixes: 2
Registered: ‎19-12-2016

Re: Drops and absurdly low downstream SNR


I've dropped you a private message, If you could reply back to it with your username I'll rub a few checks on your line to see what's going on there.



 Ben Devine
 Plusnet Help Team
Posts: 17,723
Thanks: 598
Fixes: 168
Registered: ‎05-04-2007

Re: Drops and absurdly low downstream SNR

The SNR is at a target of 6db and is currently sitting just above this. How's the line performing now?


  Upstream DSL Link Information Downstream DSL Link Information
Loop Loss: 11.8 20.0
SNR Margin: 7.5 6.9
Errored Seconds: 1 0
HEC Errors: 0  
Cell Count: 484 590
Speed: 1040 15348
Maximum Stable Rate (KBPS): 15904 Fault Threshold Rate (KBPS): 12723
Mean Time Between Retrains (Seconds): 86400 Mean Time Between Errors Upstream (Seconds): 71
Indicative Line Quality: G Mean Time Between Errors Downstream (Seconds): 14400
If this post resolved your issue please click the 'This fixed my problem' button

Former Plusnet Staff member. Posts after 31st Jan 2020 are not on behalf of Plusnet.
Posts: 78
Thanks: 1
Registered: ‎26-01-2011

Re: Drops and absurdly low downstream SNR

Hi Chris,

       Thanks, it does seem to have gone back to the usual behaviour in the last couple of days. (It did just drop briefly a couple of times in the last half hour, but I'm guessing that was something deliberate at your end?) And Ben just set the target to 6, so I'm hoping it will stay there for a while.