Strange ADSL Dropous - Any ideas? (Pretty Graphs included)

Hi All

Really hoping some DSL exports or even lurking BT engineers get to see this...

In summary I have frequent losses of sync on my line. My line is an average distance from the exchange (not sure exactly) and line attenuation is always pegged at 39.6 down and 22.1 up. The SPEED of my connection is fine, normally ~10mb, but can reduce to ~6mb if DLM kicks in due to frequent drop-outs.

Things tried so far:
- BT MK3 Faceplate
- 2x different modems, exactly the same behaviour.
- Disconnection of internal telephone wiring past master socket (I don't use it anyway)
- Changed twisted pair to property
- Changed twisted pair from cabinet
- Changed twisted pair from exchange to cabinet
- Visual inspection of exchange port and changed what is possible without a full lift and shift.
- Messing around with an AM radio set to 612Khz MW, nothing abnormal at my property.
- No REIN detected by Openreach on the line.
- Quiet line test is always perfectly quiet, even when internet is disruptive. Using the phone/etc has NO impact on my broadband.

Attached is a detailed graph of a 'typical' day. The data is gathered from a D-Link DSL320-B and I have not used routerstats due to it not properly supporting Linux (Wine is not Linux support).

>> Main Graph <<

A series of purple crosses marks a blackout. A single purple cross is not a blackout, its just that my computer failed to hit its test page once. There is one blackout (a big one where DLM adjusted my SNR margin) that is not "shown" on the graph but it happened.

SNR margin scale on the left
HEC errors scale on the right
HEC errors corrospond to DOWNSTREAM HEC errors, UPSTREAM HEC errors is always pegged at 0.

What this tells me:
- It isn't a HAM radio operator. Infact it isn't any sort of REIN or SHINE. There are no sudden or major drops in SNR margin.....
- ... however SNR margin does seem to drop SLIGHTLY for a while before a drop-out. This should not cause an issue on the 9db profile as it never went below 8db, but still died in a big HEC error-y mess.

Like here:

Dropout 1: Graph Dropout 1 SNR margin gets a tiny bit worse before the big drop. HEC errors begin rising.

Dropout 2: Graph Dropout 2 SNR margin gets dangerously low all evening, again HEC errors start to rise and finally bang. This time DLM decides to move me from 6db to 9db.

Dropous overnight: Graph Overnight Drops Loads of dropouts throughout the night, the SNR margin seems 1DB down from target during the unreliability but it IS still at 8db which is more than enough! After the re-sync at 07:15 AM the SNR margin seems more consistent and connection reliable.

I must re-iterate that even though there seems to be a slight link with SNR margin and drops, the SNR margin is NOT below spec (on the 9db profile at least) and is NOT dropping like a stone, only a tiny bit here and there.

... so, any ideas??? For the record, my ISP is working with me on this (thank god) but they are getting stumped now. They are offering a lift and shift next but I want to be sure my graphs correspond to a broken DSLAM port before going ahead with days of downtime.

Cheers !

Should also mention, that more frequent dropouts during early hours of the morning is a pattern (happens every day).

This is an example of a GOOD day. Some days can have more than 20+ drop outs and 10 of them being when I am trying to use it (17:30pm - 23:00pm)

Edited by deleted (Sun 07-Feb-16 11:37:29)

Judging by the views/comments ratio people have as much clue about this as I do...

My ISP called today and offered a lift and shift. Luckily for me they seem to be really driving my issues with Openreach now

Anyway just for giggles heres the next 24 hours (and the last I'll add):

>> Next 24 hours overview <<

>> Dropout 1 SNR margin seems to have little signifficance with this and many other drops

>> Dropout 2 A drop followed by a weird re-sync. Upstream has synced at a higher speed (and lower SNR margin). Downstream back down to SNR margin 6db but only 6mbps.

>> Overnight Drops The usual many drops in the early hours. One drop caused a stupid amount of HEC errors ruining the graph. Looking closely, same as all the other drops, they are always accompanied by between 100s-10,000s of HEC errors.

Anyway, I'll post back if a resolution is ever found... just for the people who end up here from Google.

As far as I can see, you haven't changed the modem, the modem cable or the master socket. Everything else perhaps, so maybe one of those and a lift&shift is all that's left, before migrating to a different ISP.

I've tried a selection of 3:

A D-Link DSL-320B using 1.06 firmware (standard D-Link)
A Buffalo WBMR-G54 running OpenWRT
And some old [censored] Linksys thing I had lying around

All the same

Also the BT MK3 socket is new, and BT gave me a new RJ11 cable too.

Thanks for the reply anyway - if the lift and shift fails how would migrating to a new ISP help if its over the same line? Just out of interest as I still don't really get how ADSL works.

If the other ISP has their own DSLAM then the ADSL and how it handles noise may be configured differently.

Also none of those modems have a memorable reputation for ADSL performance, the old 2Wire kit was usually the go to kit for problematic lines.

So just a bit of an update on this.

We had the lift and shift done - no improvement.

This left me a bit baffled. New twisted pair from house to exchange and new port but still random drop outs (noticeably worse with rain (not rein, RAIN lol)).

So at this point I removed the plastic cover from the DP on my house to discover that my line was still on its original twisted pair. Openbreach just pretended they did it. They seem good at lying on notes.

Since then my ISP has been fighting to get the line checked and crimps/pairs changed but with no success. My ISP has even been on the phone to Openreach engineers that have been to my house asking them to do at least something but they point-blank refuse. "Our tests show the line is fine, so we are going now..." oh great must be imagining the 20 drop-outs per day then. Idiot.

In summary:
The problem is my line, 99% sure.
My ISP really have handled this 10/10 and have done all they can. I dont even need to chase them, they call me saying they notice the line is still poor.
If you have an Openreach line that is faulty but not to the point it has totally failed, then god help you.

Changing to a modem that handles noise better isn't going to help as the problem isn't noise. Also changing ISP isn't going to help as we only have BT wholesale here no other LLUs

Also changing ISP isn't going to help as we only have BT wholesale here no other LLUs

Which ISP are you with?

Zen at the moment !

How does 'removing the DP lid' prove you are on the same pair ?

If your ISP is doing so much, and I believe yours has a good reputation, why have they not arranged for further visits ? There is no point 'ringing the previous engineers', they are unable to just return to a previous task like that.

Hi

Just to clarify:

Removing DP cover: Check if crimps look old and [censored] - this would disprove them being changed recently. Actually the pairs were held together by insulation tape, which suggests BT have not even checked it at least whilst I have been in this property.

Zen have arranged approximately 8 engineers so far plus a lift and shift and I am sure they will not hesitate to arrange more if required.

They also did not ring previous engineers, they rang the engineer whilst he was at my house. Actually it was me who rang zen to speak to the engineer as frankly I am sick of taking time off work for engineers to turn up and do sweet FA.

In reply to a post by rlees85:

Hi

Just to clarify:

Removing DP cover: Check if crimps look old and [censored] - this would disprove them being changed recently. Actually the pairs were held together by insulation tape, which suggests BT have not even checked it at least whilst I have been in this property.

Any chance of a photo?

In reply to a post by rlees85:

Removing DP cover

I'm surprised you have a DP on your house.
How many other premises does it serve?

Edited by deleted (Sun 06-Mar-16 17:54:26)

Certainly...

Piccy

Also DP might be the wrong term, apologies, it only serves my property

About the photo, BT have sorted this since on the last engineer visit. It just annoyed me a lot of the previous engineers said they changed and checked this stuff on their notes but clearly had not! The problems with ADSL persist however... I tried to get him to change to a new pair too (more things tried, more likely to work!) plus with my 7 previous engineers its the only thing left to try lol. Anyway he flatly refused

In reply to a post by rlees85:

About the photo, BT have sorted this since on the last engineer visit.

So it's no longer like that but still uses the same pair?

So not a DP at all then, just a connector bend no.4

So it's no longer like that but still uses the same pair?

Well it still appears to be on the blue/white of the five pair UG lead in, this doesn't prove at all that the pair from the UG DP back to the cab hasn't been swapped out at all.

Yes, its still on the same pair as what is pictured, but now with the correct BT crimp installed.

I have no idea where the UG DP is and don't really want to go poking around what isn't mine to poke around with so I am not sure. I have been told it has been changed. So the only thing that has not been changed (if notes are correct) is from the 'lead in' pictured to the 'UG DP' - which I assume sits between my house and the cabinet somewhere.

Guess will see what Zen say next week and pray the next BT engineer will be keen to get this sorted.

By the way, when I say 'my house' its a rental property, I have been here like 4 months. I am assuming it has a long history of bad internet if one of the previous tennants felt to do some DIY work on the line lol

Edited by deleted (Sun 06-Mar-16 23:11:45)

it should be noted that the pictured black tape was clearly not the work of Openreach staff. They all carry the required crimps, which are simplicity itself to use, so why twist the pair up and tape up the result if you have, to hand, ind the same tool bag as the tape, some crimps ?

That no one had previously checked in the connector bend no.4 IS a sad reflection on Openreach though.

Yeah I am sure that wasn't the work of Openreach but the point is they should have spotted it after seven engineers.

Anyway, got engineer number 8 tomorrow!

I appreciate all the posts on this thread.

The last Openreach engineer was very knowledgeable and did further tests and even changed the D-side for good measure.

The fault still persists.

It has recently been revealed that no lift and shift has been done on my line. Zen are trying to do one. But there is no down time, and I thought there was for lift and shift. So I am suspicious. Either that or I am getting mixed up with TPM.

If this fails, I am going to migrate to another ISP, preferably on a different LLU.

At my wits end. But I need workable Internet... So I am not having a dig at Zen. I just need a working connection. ISP is the next thing to try. It has been 4 months after all.

There ought to be a guide for all of these terms somewhere like:

D-side = cabinet to property pair
E-side = cabinet to exchange pair
Lift and Shift = god knows
TPM = new pair going into Exchange to DSLAM
etc

Edited by deleted (Mon 14-Mar-16 22:55:08)

Lift and Shift = god knows

A lift and shift, the service provider allocates and makes live a different 'port' for your broadband to be connected to. This is often, though not always, arranged by a visiting Openreach engineer during an SFI task .... They will have co-op'd with the CP and agreed this needs to be done.

There's a possibility that it might be your router. I have had persistent dropouts on my ADSL connection for several years that, frankly, I have done nothing about except that line tests always returned 'no fault'. When it happened, my usual response was to reboot my PC and router and that would fix it. When the dropouts became more frequent, I noticed that the LEDs on the router were not achieving full brightness when I switched it back on, so I bought a new power brick. That made absolutely no difference. Eventually, I realised that the router worked just fine when my desktop was not plugged in (to an ethernet port). I now have everything connected wirelessly and I've not had a single dropout (and the LEDs achieve full brightness). Is it the router or the PC that's faulty? I don't really know but I suspect it's the router. It's a Netgear DG834N and I'm on ADSL2+, btw. Just a thought.

Edit: Of course, some dropouts may have been due to line conditions or engineering work but so far, so good.

Edit: Connection time currently 65 days.

Edited by micksharpe (Fri 18-Mar-16 16:03:01)

Again thanks for the clarification Zarjaz. I assume you must work for BT you seem very knowledgeable?

Sadly BT refused the lift and shift so my ISP has had to order a TPM. No internet all weekend lol but I am not moaning at least things are progressing .

It is a shame that Openreach refuse to do anything bar a 5 minute ADSL test and a PQ. After that you are more or less told you are imagining the drop outs. It is also a shame as I have met engineers who are very good who given the resource and permission would get to the bottom of these kind of issues within a few hours.

Meh.. anyway I'll post back if it works or not.

It is not the router, I've tried a fine selection of routers already

Probably a long shot but did you know the previous tenants or possible to get in contact with them?

Maybe if they were on LLU they would be able to tell you if they had problems or not. Changing to an LLU provider may work, but then it depends where the fault lies

Asking people if they have had broadband problems is often a fairly fruitless experience in my opinion. They happily tell you, at length, about when they couldn't send those photos to Aunt Doris in Basildon that time. Also, you have no way of knowing if they had their kit set up correctly or not. So any data collated will be fairly worthless.
I should qualify this by saying I have knocked on the doors of folk who lived next door to a huge REIN source, but "had no problems at all".

Nah I didn't keep in touch with the old tenants and agree its probably fruitless to ask a question like that.

Anyway my broadband is back on. Funnily enough I have exactly the same 9db profile applied as before and still getting tonnes of errors/dropouts.

Failed to ask Zen if the TPM was completed - I spent 1 hour and 20 minutes on hold and gave up. I assume they must have had a major outage themselves as normally can get through after 5 minutes tops...

I am thinking if the TPM was carried out, changing LLU is going to be a totally pointless exercise.