cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
Highlighted
Contributor
686 Views
Message 1 of 16

Permanent 9dB to 10dB Signal/Noise on Infinity Line

Hi Guys,

 

I've had BT Infinity (up to 52MB) over a year now and the Home Hub says my line is capable of over 50MB, the connection is never much over 40MB. The reason seems to be the signal to noise ratio that is set on my line is way too high at 10dB.

 

The signal to noise ratio has always been 9 to 10dB since day one of service. I have a Home Hub 5B running now and this seems reasonably stable, although it's never gone more than 10 days without quickly re-starting at some random time of the day or night. I previously has Hub 5A which gave similar results. It too never went more than 10 days without a WAN restart.

I changed to the 5B as I think it has a different Broadcom chipset, although the line speeds and performance are not a lot different.

 

There is no problem with my phone line - quiet line is silent for example. I am not aware of any interference issue either.

I called 150 and reported this last night in the hope someone can reset the exchange equipment to 6dB signal to noise. 

 

I would be grateful if any distinguished gurus's would comment/provide their thoughts on this signal to noise issue that is slowing down my speeds - please.

 

Whilst writing, I am also thinking of changing the HH5 to a non-BT router next year, so if anyone has any recommendations for a different, more relianble VDSL2 modem/router, I would also appreciate that.

 

Thanks. Here's the helpdesk screen:

 

bt-hh-screen-grab.jpg

0 Ratings
15 REPLIES 15
Highlighted
Distinguished Sage
Distinguished Sage
678 Views
Message 2 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

The reason your SNRm is so high is that DLM has banded your line at 44M in an attempt to give you a stable connection. DLM is notoriously reluctant to remove banding when line conditions improve. Changing router will have no effect. Unfortunately, the only way to get a DLM reset is if an Openreach engineer visits and clears a line fault.

0 Ratings
Highlighted
Contributor
620 Views
Message 3 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

Thanks.

Would this issue at the DLM be caused by the home hub's WAN disconnections (estimate these at one a week)? Seems odd though as the max speed was 40MB when the line was first provisioned (upgrade from ADSL2+) and went up to 44MB at some point over the last year. No Openreach engineer has ever visited to install the service, so it seems banding has been there from day one!

Question though. If BT are upgrading all users speeds how can they do that if these banded lines are out there. Can they manually reset the DLM port? Or do manually banded lines not get the speed upgrade!

In the meantime, I will wait to hear back from someone at BT to see what they say and what they're prepared to do.

Finally, if I pursue this and report it as a fault, am I going to get charged, if they say the line is working within limits.

Many thanks
0 Ratings
Highlighted
Distinguished Sage
Distinguished Sage
612 Views
Message 4 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

you attainable speed is not high enough so you will not benefit from speed upgrade

 

if you report a fault but no fault found which is probable then engineer will not reset DLM



If you like a post, or want to say thanks for a helpful answer, please click on the Ratings 'Thumbs up' on left hand side.
If someone answers your question correctly please let other members know by clicking on ’Mark as Accepted Solution’.
0 Ratings
Highlighted
Recognised Expert
602 Views
Message 5 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

1 discon per week is nowt to get concerned about.

___________________________________________________________________________
If you like a post, or want to say thanks for a helpful answer, please click on the Ratings star on left hand side
0 Ratings
Highlighted
Contributor
568 Views
Message 6 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

 

Thanks Guys.

So do I request an engineer visit to scope the line performance and reset the DLM?

I paid (from memory £55) for VDSL installation, but nobody visited on-site and I have never called an engineer out in 18 months. The issue has been there from day one, so whoever set up the DLM initially set it up for max 40MB and after a year and a half it is at 44MB. 

I would appreciate your advice on what to do next.

 

Here's the line dump, which clearly shows "IMPACTED" status:

BT-line-profile-crop.jpg

 

0 Ratings
Highlighted
Distinguished Sage
Distinguished Sage
563 Views
Message 7 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

Nobody 'set it up', DLM is an automatic system that continuously monitors your line and sets your speed accordingly. Unfortunately it occasionally gets stuck but unless an engineer finds and clears a fault, Openreach will not allow DLM to be reset.

0 Ratings
Highlighted
Distinguished Sage
Distinguished Sage
562 Views
Message 8 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

your conenction speed is within your estimated range so not a problem and from what you say your line is ok with maybe 1 drop in conenction per week  what fault are you going to report remembering if no fault found then engineer will not reset the dLM



If you like a post, or want to say thanks for a helpful answer, please click on the Ratings 'Thumbs up' on left hand side.
If someone answers your question correctly please let other members know by clicking on ’Mark as Accepted Solution’.
0 Ratings
Highlighted
Recognised Expert
551 Views
Message 9 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line


@m0sbf wrote:

Here's the line dump, which clearly shows "IMPACTED" status:


But not for your line, which has no Bridge Taps.

___________________________________________________________________________
If you like a post, or want to say thanks for a helpful answer, please click on the Ratings star on left hand side
0 Ratings
Highlighted
Contributor
530 Views
Message 10 of 16

Re: Permanent 9dB to 10dB Signal/Noise on Infinity Line

Oh, thanks, my misunderstanding.

0 Ratings