Constant loss of sync

So I have a line at one of my sites in central London which has been 'ok' for a while now... Over the past 3 months it's been down more than it's been up due to persistent loss of sync events.

BT are not interested - and there is no voice fault.

The line is already pegged down to 8mbit on a fixed profile.

Line stats are:

ADSL Mode: ADSL2+(G.992.5)
Up Speed: 1136000
Down Speed: 8124100
SNR Margin: 14
Loop Att.: 30
Status: SHOWTIME

I'm going to force it down to G.DMT tonight and see what happens over the next few days as I suspect its actually an upstream issue.

The irony is that this is the last xDSL line in use on that site - all other services have been migrated to Virgin Media as BT where unable to provide anything like a usable service for over a yr now. This line however is needed for some out of band management and testing so is rather important...

We are Cab fed via our own DP & 20 Pr with a fully UG route from Exchange to Cab to us.
Exchange: BERMONDSEY is served by Cabinet: 52
Speed checker says I should expect 17Mbit, but left to its own devices the line is so bad it will only get around 11 if memory serves from before it was pegged down, and when it did it would only end up back on a banded profile anyway, or unusable.

I'm guessing its a cable or a REIN problem - but BT have attended many time and never been able to find a fault, nor been interested in a lift an shift (of even the E-Side) (Which makes me think we are pair limited)

Disconnections are generally every 10 mins or so and the only thing of note recently has been the weather in London with quite a bit of rain) but getting someone out when its raining is a joke (its a joke to get a competent engineer in the 1st place these days )

Has anyone got up to date PCP data that might indicate if we might see FTTC any time in the future? Failing that any ideas how I might kick Zen and in turn BT into touch to get this resolved - or shall I look at removing that line to VM as well and try and get someone who understands what a 'static IP address' actually is, and the fact we can't use the 'Superhub'

Ideas?!

In the future yes, cabinet may well be part of the commercial extension programme in London. No dates.

Virgin Media Business are meant to be the ones you pay more to understand what an IP address is, but the superhub is needed to terminate the coax cable service, unless you pay more for a full fibre one i.e. leased line.

AAISP are generally the best ISP for DSL services when things are a bit flaky, and another option is to get an ADSL modem that gives you more control over some of the aspects i.e. target noise margin

Cheers Andrew... VM Didn't have a clue even after setting up 2 other line at the same address - they insist there is no static IP addresses....

I may try a migration to A&A to see if they can fix the issues then back again if they can get things sorted. That site looked a VM fibre but they wanted so much to bring it literally over the road it wasn't worth it - they just needed something to get them away from BT's network and the persistent problems.

I'm hoping there might be some movement on an improvement for the area as they have just built a num ber of blocks of flats less that 5mtr away which I don't think have service from anyone.

I'll keep an eye on things anyway - cheers for the reply.

I also forced the line to G.DMT and now I get PPP drops every 10 min instead of loss of sync. lol - how did we let BT give us such a poor platform...

Edited by IamQ (Wed 06-Jan-16 18:26:02)

I would echo MrSaffron Suggestion, make sure you haver a good ADSL Modem, My link to the exchange is not very good quality (old and long). After struggling to get a sync close to 8M for years I got my self a Billion 7800 I now get and KEEP sync at 11M. Being able to tweek the SNR made the difference

Upstream Downstream Sync Rate BRAS Profile Interleave
1084 9925 11250 TR101 Auto

DMT Status No Defect
Operational Mode ADSL2+
Upstream 1096
Downstream 11273
SNR Margin(Upstream) 6.4
SNR Margin(Downstream) 0.6
Line Attenuation(Upstream) 20.8
Line Attenuation(Downstream) 37.5

It's not the modem. It's the line(s)...

I had 5 other ccts all off the same bundle and due to faults on each one they have slowly got rid of them all and moved to VM. Since then there's been no issues... Answer will be to get rid of all BT services I suspect...

I can't play hunt the working modem - this is a commercial install and hardware is fixed across all sites.

Edited by IamQ (Fri 08-Jan-16 17:57:24)