ADSL speed, TAP3 and Business Support

At 00:15 on Thursday 21/08 I raised a question whinging about my much less than expected ADSL speed.
At 15:30 on Monday 25/08 Plusnet responded by phone and the question advising me to switch router, filter, plug in to the test socket and run a TAP3 test.
Since then I have switched from a trusty old Netgear DG834G4 to the brain damaged PlusNet Technicolor TG582N (I could not get port forwarding to work, settling for putting my firewall (FreeBSD+IPFW) into the router's DMZ) connected to the test socket with the supplied cable and filter and normally no phone connected. This has improved speed a lot, but still not to Be speeds at their best under similar circumstances (short 100m EO lines, Annex M).

In particular my upload speed is down by 0.5 Mb/s.

I see around a million FEC errors per hour, and there is a slight constant hiss when performing a quiet line test with a corded phone and headset. The hiss is also present when the router is disconnected. I assume that this less than perfect line causes the low Annex M upload sync rate, slightly low download sync rate and interleaving.

With a Windows laptop connected to the router and my firewall disconnected the BT wholesale speed test consistently shows my upload speed as below threshold and invites me to run the tap3 test, but when I do my browser times out, which seems to be a known problem.

I have updated the question with my findings throughout, but Business Support have yet to get back to me.

Any advice?

I am unhappy:
With the time and effort that this is taking.
That Business Support only work 08:00-20:00, whereas I normally rise shortly before starting work at 18:00 and do not have time to call them till rather later. Residential Support do eventually answer the phone but can not do much for Business customers (different systems?).
That Business Support seem rather slow to respond to question updates, and have asked me to perform a test which they know does not work.
That I have signed up for 24 months (barring future price rise get out of jail free cards) for a quite expensive package (Business, Annex M, priority - both these last are around £10 a pop), which is not as good as I expected.

On the other hand, while PlusNet are a BT subsidiary, so far they seem much better than BT in general and BT Business Local in particular.

TG582n stats

xdsl info expand=enabled
Physical Layer Statistics:

Modem state: up
Up time (Days hh:mm:ss): 0 days, 20:10:52
xDSL Standard: ITU-T G.992.5
xDSL Annex: Annex M US 56
Channel Mode: Interleaved

Number of reset: 1

Chipset Vendor info (G.994.1): Local Remote
Country code: B500 B500
ID: BDCM TSTC
Specific: 0000 0510

System Vendor info (showtime): Local Remote
Country code: 0F00 0000
ID: TMMB ----
Specific: 3C61 0000

Bearers generic info DS US
Payload rate [Kbps]: 20727 2070
Attenuation [dB]: 4.5 5.0
Margins [dB]: 4.4 7.1
Output power [dBm]: 19.4 12.4

Number of bearers: 1
Bearer 0 DS US
INP [DMT symbols]: 1.07 0.11
Delay [ms]: 5.65 1.60
Depth []: 96 0.00
R: 16 0

G.997.1 Statistics (Current):

Failures:
Line failures Near end
Loss of signal (LOS): 1
Loss of frame (LOF): 9
Loss of power (LPR): 0

Performance monitoring:
Line PM: Near end
Error second (ES): 13

Channel PM: Near end Far end
Bearer 0:
Code Violation (CV): 2 14
FEC: 21203537 17

ATM data path PM: Near end Far end
Bearer 0:
HEC violation count (HEC): 1 N/A

TBB speed tests

Date Down TBB Down HTTPx6 Upstream IP Address ISP

Wed 27/08/14 01:20 17.13 Mbps 16.95 Mbps 1.82 Mbps - Plusnet

Fri 01/08/14 08:54 20.90 Mbps 20.37 Mbps 0.91 Mbps - BT

02/01/12 22:09 Mon 19936 Kbps 2352 Kbps - Be

Did you order an annex M service?

Or is modem left on annex m from be days?

In reply to a post by MrSaffron:

Did you order an annex M service?
Or is modem left on annex m from be days?

Yes, I ordered Annex M.

The modem is a new PlusNet supplied TG852n, with minimal configuration changes (disable WiFi, change LAN address, put my firewall into the DMZ as I could not get port forwarding to work). I switched to that on, I think, Monday.

Prior to my move away from them, I had BT ADSL on that line (Annex M not being available from BT was one of my reasons for switching).

Something that may be significant. I have two active ADSL lines here (mine and a Talk Talk Business ADSL 8 Mb line supplied by my employer). The cable to the PlusNet master socket line comes out of the back of the TalkTalk master socket, which is fed by a single cable to what was once the master socket until I had ISDN installed. All wiring done by BT or their contractors.

Could my speed problem and faint hiss be crosstalk between these two lines, which probably run very close together all the way back to the exchange?
Can anything be done about it?

Easy to tell does the hiss go away when one line has all its xDSL kit unplugged?

At a guess you may find the way BT Wholesale configure its Annex M and the TG582n just do not push things to the maximum. Be was very good at tweaking its DSLAM configurations and maybe pushing the power limits of the ANFP to the absolute edge of the envelope to squeeze every ounce.

(Have known some SDSL services to ignore the ANFP in years gone by to get a better range)

Annex M is rare enough that possibly not so widely tested too by ISP and modem manufacturers and with the rise of VDSL2 is almost a legacy thing now.

The hiss, and a few whistles, is present on both lines 10 minutes after unplugging both routers from their lines and power supplies.
PlusNet phoned me this evening, and a SFI engineer will visit tomorrow afternoon.

Thanks for your advice.

Yes, few do ADSL Annex M any more. I wish I were not a legacy user. As far as I can tell from the ConnectCheshire maps, this small EO patch around the WMALS exchange is under evaluation, so there is some chance that I may be able to get FTT*. The half of this post code on the other side of the road has FTTC.

Well, the engineer came on Friday afternoon, and spent hours in the exchange today.
Net result:
Download FECs reduced to 80,000 and hour, Still a not very good download speed.
Upload Annex M sync of 1725 kbps, and TBB and BT Wholesale speed tests of 0.88 MB.
I am unhappy (8-(

Edited by awontroba (Mon 01-Sep-14 17:57:57)

Wrap up report.

Communication with Plusnet by ticket is slow but effective.

Plusnet tried hard, and arranged two SFI visits, which have not cost me anything.

I had at least one lift and shift, and the second SFI engineer, after closing the call, went the added mile and arranged a cherry picker and exchange engineer to switch the line from my DP to the exchange back to my original (excellent with BE) residential line. Tea and biscuits may help, but a bottle of wine helps more (8-).

Despite all this I was left with a line with a startlingly high number of download FEC errors and the BT Wholesale speed test (just) failing for uploads. Something, somewhere, is noisy and I doubt that it will ever be found.

The very faint noises I could hear in a quiet line test were probably due to the ancient corded phone I was using.

A MK3 faceplate and ferrite cores on all cables into the Plusnet router had no noticeable effect.

Switching to a £25 from EBay Draytek Vigor 2820 router, with the latest ADSL-M firmware (3.3.7.5_2471201) marginally improved my upload rate, which now just passes the BT Wholesale speed test.

The 2820 has also allowed me to load balance my previously very lightly used Talk Talk ADSL "up to 8 Mbps" line.
Current / Peak / Speed Current / Peak / Speed Current / Peak
WAN1 CENSORED 1353 / 2240 / 1852 1117 / 16902 / 15580
WAN2 CENSORED 21 / 640 / 532 5 / 5668 / 5890
Total 1374 / 2880 / 2384 1122 / 22570 / 21470

Oh for FTTC / FTTP. I am close to the WMALS exchange with only EO lines available. No news yet from Connecting Cheshire, but I live in hope. I am told that some senior BT Management live nearby and are also frustrated that they are stuck with ADSL.