What's happening to my line?

Hello all. Within the last few days I have noticed my speed (at the modem) drop from a solid 40000 to 39997, but the upload move from 9997 to 10000. The noise margin for download stayed at 10.2db, the upload went from 10.1db to 12.1db. Since then the download speed has dropped to 34999 but the snr went up to 12.5db. Upload is at 9998 and the snr remains at 12.1db.
I have noted in the log that the vdsl signal has dropped at approximately 2:20am the last few nights, so I'm guessing that's why, but I don't know why that would be? Been rock steady at 40000/9997 for years. Got the Sky SR102 btw. Any ideas? Thought they might be preparing for my speed upgrade!

The changes between 39997/39998/39999/40000
are perfectly normal.
They are all a normal sync for a 40Mb package.

The 34999 however is a DLM capped/banded figure.
DLM usually applies banding for too many resyncs in a set period of time.
Banding can take months/never to automatically remove itself.

My advise is do NOT manually resync the line "to see if the banding has gone".
A manual resync will never, ever, result in DLM making a positive change to the line. It treats resyncs as instability and may make it worse.
DLM will force a resync when it wants to remove the banding.

I actually saw DLM remove banding within 24-48 hours on a line a few days ago which isn't the case enough of the time.

Does the log report how often the DSL signal was dropped?

Hello John. Thanks for the reply. The logs only seems to show the connection dropping once a night for a few nights. Both times around 2am. There are a lot of iprenew lines in there (about every 30 mins or so). As I'm due the free upgrade by spring, is this latest development likely to affect the upgraded speed I get do you think? Will the line remain banded after the upgrade? Thanks.

Hmm, short answer is I'm not sure.

I recall WilliamG upgrading from 40/10 to 55/10 in the past and although the DLM appeared to reset (G.INP was removed) the banding remained in place.

The user adslmax had banding applied on 3rd Feb and it was removed on the 4th so it might well remove itself tomorrow.

Seems pretty harsh to apply banding for a single resync in 24 hours.

I know if reporting a line issue people have said to mention voice as opposed to Internet for some reason. Do you think its worth me doing that? Thanks again.

I'd leave it 24-48 hours as it may well sort itself.

Failing that and you do wish to contact your ISP then you need to report it as a broadband fault.

In the past the 1 of the only ways to get a DLM reset was to have an engineer come out and have it done.
Engineers who were attending voice faults did not have the option/ability to reset the DLM. That could only be done on broadband faults.

They introduced a trial a while ago where the ISP could request a remote DLM reset without the need for an engineer.
I don't know if this is still in trial phase or if Sky were part of the trial.

I would still wait 48 hours before contacting the ISP if that's what you wish to do.

Hi

Reporting a voice fault is only useful if you have noise or crackles on the phone line. This physical fault will usually cause major issues with ADSL/VDSL (usually more than you are seeing), but reporting it to your ISP gives you the run around of new routers, reboots, use the test socket etc. Reporting a voice fault (which crackles are really, affecting voice calls) is a more direct route to getting the problem fixed. Once the underlying connection fault is fixed, your VDSL will start working fine, although you may still have the issue of a banded line etc, but this should self correct (hopefully).

In your case, unless you do have crackles on the phone, what fault can you report as a voice fault? There isn't one.

At the moment you don't really seem to have a fault as such. DLM can intervene for many reasons, and fighting DLM is often a losing battle.

Just wait it out and see what happens is the best advice at the minute.

Regards

Phil

John/Philip - many thanks for your quick and insightful responses. Much appreciated. I shall wait it out and see how I get on. Shall let you know how it turns out.

The IP renew lines in the router log are perfectly normal for a Sky fibre connection because they have a 60 minute DHCP lease time. You only need to worry if the lease doesn't renew within the 60 minutes then the connection will drop.

Thanks Simon, I didn't know that! 👍