DSL Speed reduction :(

I have nothing plugged in at all - the router is plugged directly into the master socket, the master faceplate is removed as well so all extension wiring is disconnected. This is how I've run it for years.
 
It sounds like just general instability because the line is long. If the line is a bit flakey DLM will kick in and raise the SNR, but as a side effect it can be harder to sync up with a high SNR target.

If you went down the route of reporting it as a fault, assuming there is no 'fault' on the copper line as such, an engineer might be able to improve the stability by changing a pair, or putting in a filtered master socket (aka SSFP/NTE2000) - or both. But do bare in mind there is a chance the engineer will test it fine and mark the visit as chargeable. I'm not sure on the specifics of chargeable visits on 'long lines', so it might be better to check this with your SP before getting an engineer out.

If you had the DLM profile on the DSLAM hard locked to 6dB SNR, your sync speed would be roughly the same as before (~2meg) but it's stability would vary, sometimes it would be fine and stable for a week or more and other times it'll drop daily - but it should only be down momentarily whilst it re-syncs.

You may find it difficult to get your SP to get a hard DLM profile applied, in fact I'm not even sure if BTw will officially do it. Although if I were on a line with your stats (mine isn't a million miles off), I would prefer having the SNR target set to 6 and deal with a little instability ;)
 
[TW]Fox;15903298 said:
It's not something I've really had before - certainly not like this. My line worked perfectly for several weeks at the higher speed, as well.

Yeah it probably was, but DLM isn't the best system in the world and longer lines can vary over time. Sometimes they can be fine for weeks on end, and then go really flakey for a while and then back stable again.

Have you thought about picking up a filtered faceplate which plugs straight into the test socket? This is effectively what an engineer might fit, and it might help - but at ~£15 it might also do sod all :(

One option (if you don't want an engineer to visit) would be to speak to your SP, and see if they can get BTw to either reset the DLM profile, or get it locked at 6 or 9dB and see how you fair.
 
2 wire 2700HGV routers can be very good on a long line.

Will probably need to get one that's unlocked though as I believe they are locked to BT internet, being a BT router.
 
Tried monitoring your sync speed and noise margin over a longer period to see if there's any correlation with weather, devices being powered or other events?
I had similar symptoms and had convinced myself the problem wasn't at 'my end' but ran routerstats for a few weeks and managed to work out my problem was down to a monitor PSU. The PSU was always powered but caused the problem several minutes after the occasionally used monitor came out of standby. Interesting to see others have found (switched mode?) psus to be the cause of their troubles too. Have since found http://forums.thinkbroadband.com/ds...834g-v4-switch-mode-psu-causes-downspeed.html that you may find interesting.
If by chance it is caused by mains-borne noise affecting the router (mine was a Sky DG834GT) maybe try a different make of router, or powering the router via a mains filter?
Good luck - I know how annoying it is.
 
2 wire 2700HGV routers can be very good on a long line.

Will probably need to get one that's unlocked though as I believe they are locked to BT internet, being a BT router.

This was by far the most stable router I've used on my line, but the sync speed was noticeably lower than the DG834GT which isn't bad in terms of stability to be fair.
 
Do you have a filter on the socket before the router?..

-You should have one

Yes, I do.

Connection is once again stable and has been since last night but its still only 1300k. I contacted Plusnet 36 hours ago to ask them to reset the SNR on the line but despite the 'Average ticket time' being 10 hours they've not seen fit to bother to reply.
 
I honestly think the only solution to your connection problems is to move house. :p

So you don't think the profile has been changed back then?
 
<3 eclipse, you call up a basic phoneline with no menu's, speak technically to the geek the other end about BRAS's and SNR's etc, he does it while you are on the phone instantly while you both have a chat about geeky ADSL stuff, no need for a ticket number or anything like that.

GL with plusnet :(
 
Unfortunately changing your SNR isnt a manual process thats as simple as us pressing a button, BT can change it but only do so generally as part of a fault investigation if something is wrong or stuck. Actual changes in SNR are done by the exchange with a piece of equipment called the DLM. The DLM will update your SNR based purely on the noise and errors showing on your line at the time your modem syncs up to the exchage.

As such the best way to attain a better sync rate and lower SNR is to restart the router, if however the rate does not change this does not usually indicate a problem with the DLM but with the line conditions themselves. If it does not reset to a lower level there may well be a good reason for this meaning any forced change would just instantly revert back anyway.

So they wont do it. Are they right to refuse?
 
By manually setting the SNR Percentage to 5% using the custom DGTeam firmware on my DG834GT, I can get:

ADSL Link Downstream Upstream
Connection Speed 1952 kbps 448 kbps
Line Attenuation 63.5 db 31.5 db
Noise Margin 10.4 db 8.0 db

But I used to be stable without having to do this and with a lower noise margin! I dont understand whats changed. Obviously unless I can get it back to the 2240ish it usually connected at I presumably wont be able to get my old IP Profile of 2000kbit back? :(
 
[TW]Fox;15909594 said:
By manually setting the SNR Percentage to 5% using the custom DGTeam firmware on my DG834GT, I can get:



But I used to be stable without having to do this and with a lower noise margin! I dont understand whats changed. Obviously unless I can get it back to the 2240ish it usually connected at I presumably wont be able to get my old IP Profile of 2000kbit back? :(

Sadly, you're correct about your profile.

Check out AAISP's website. They have a pledge to fix a new customers line (IF there is an actual fault to fix) within a month or you can migrate away and not owe them a penny. They are a very, very good ISP and make an awful lot of information available to their customers, not to mention basic control over their line (like being able to set interleaving on or off, super stable etc).

AAISP
 
Last edited:
This is why I love o2, phone free phone number, ask for 3db profile, they do it instantly, whole call last about 2 mins, I don't understand why ISP's take time over doing this.
 
[TW]Fox;15909575 said:
So they wont do it. Are they right to refuse?

They are being total pleb's, and unfortunately this is kind of what i expected from a mass market "consumer" ISP - they cant be bothered basically. They can definitely change it (or can get it changed) virtually instantly, as eclipse have done it while on the phone to them more than a couple of times for me. I used to have to get it reset after virtually every period of high winds.

Is it stable with an SNR of 10? If it is then it looks like perhaps the issues on the line have passed. If so, i would get the line reported if plusnet require a fault to be raised for them to reset the SNR.
 
Back
Top Bottom