dirty line!

have turned to the brains in the forum to potentially help me solve my broadband issues,
my situation:
broadband is solid connection, connection holds for a random time normally about half an hour, connection is lost, and reestablished quickly and this repeats itself all day. sometimes more reliable ( 4hours no probs) and sometimes constantly (every 3 mins) disconnecting.

supplier o2, asdl2 only 2km from exchange, newish house, town center location. can somtimes get 11 meg down and 1 meg upload, my noise margin i think is on o2's maximum 15db?! they told me, my connection speed fluctuates all the time and sometimes is as low as 0.5 meg down and 0.3 up and sometimes 8 and 0.5 . no real consistent speed always random.

have had 3 open reach engineers out so far, have replaced, modem, master socket, line from master socket outside, maybe the line to the cabinet (next engineer will def try that), def the line from cabinet to exchange is changed and i have had a shift over in the exchange to a new place (if i have phrased that correctly).

currently going through the process of o2 monitoring my line for 24 hours before they will send another engineer out but i have lost faith in open reaches ability, plus as my problem is intermittent its generally hard to pinpoint when they are here.

any advise or comments appreciated and believe me if i could get virgins fiber optic line to my house, i would have a long time ago. have considered rein?! interference but not really sure what to listen for and have walked around like a loon with a sony radio in my street in desperation.

many thanks to anyone who reads this and can advise me to deal with my problem, 02 or openreach.

Post your line stats as reported by your router. See http://192.168.1.254/cgi/b/dsl/dt/?ce=1&be=0&l0=1&l1=0 or http://www.o2help.co.uk/router-statistics/

Have you got Sky TV?

Sounds like mine except the noise level that forces a resync happens much less often than yours and I don't lose significant amounts of speed when it resyncs other than the expected difference between day and night.

Can you hear any noise at all? You can check this without using the quiet line test number as just dialling a 0 causes the dial tone to go and you get quite a while before the nagging voice starts up.

Mine has been voice engineers as I first reported it before O2 was activated but I doubt that ADSL engineers would get any further because the problem is essentially intermittent.

So far..

Engineer..
#1 replaced the drop cable from the pole
#2 remade joints at base of pole and put in a maintenance order to replace cable down the pole (this hasn't happened yet so far as I know)
#3 swapped pair to street cab
#4 swapped pair from cab to exchange

There is still intermittent audible noise and it still occasionally resyncs - sometimes recovering with a faster sync.

I fear that yours like mine will be a long and laborious process to get a fix.

I could get cable but the cost is a lot more than ADSL so that will be a very last resort for me.

have this should be my router stats?? and yes i have sky plus, and to the other response jus tried listening and it seems quiet enough, also the openreach guys do a quiet line test when they were here, if i was u i would get involved with fibre optic as i heard its more reliable than sending large chunks of information down a thin coppery line!!

DSL Connection

Link Information

Uptime: 0 days, 10:00:36
DSL Type: G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]: 1,005 / 10,167
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.0 / 19.0
Line Attenuation (Up/Down) [dB]: 16.5 / 31.0
SN Margin (Up/Down) [dB]: 15.5 / 15.5
Vendor ID (Local/Remote): TMMB / BDCM
Loss of Framing (Local/Remote): 1 / 0
Loss of Signal (Local/Remote): 1 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 1 / 0
FEC Errors (Up/Down): 1 / 40,849
CRC Errors (Up/Down): 1 / 44
HEC Errors (Up/Down): 12 / 34

just checked them 2 mins later and this part had changed, dunno if this is important as i dunno what i'm reading:

FEC Errors (Up/Down): 5 / 43,175
CRC Errors (Up/Down): 5 / 52
HEC Errors (Up/Down): 14 / 41

Poor stats. Looks like you've got line problems. If BT have ruled out external issues, chances are there's something wrong with your own wiring. The sky box is a prime suspect. Is it filtered?

1 Error Second in total. These are okay as one-offs, but should not occur regularly.

1 Loss of Framing errors. A few of these are okay, as it may have been a one-off occurence, but they should never occur on a good quality line.

1 Loss of Signal Local errors. These are okay as rare one-offs, but should not occur regularly.

Expected download speed at your current sync rate: 1.06 MB per second (or 8653 kbit)

Expected upload speed at your current sync rate: 106.91 KB per second (or 855 kbit)

Problem: Downstream sync speed of 10167 kbit is 2285 kbit slower or 82 percent of the average for connections with the same downstream attenuation of 31dB.

Problem: Signal Noise Margin Down (15.5dB) is extremely high. Be* may have put you on this profile to compensate for a high error rate. If you know that your line is actually reliable, lowering the value to the average of 6dB should give a sync speed increase. Call Be* to change it (3dB steps only).

Problem: Signal Noise Margin Up (15.5dB) is higher than average and may be this high in order to compensate for current/previous high error rates.

Problem: There are some FEC Up errors. FEC errors are *corrected* errors, so these are probably nothing to worry about. Speedtouch routers have a habit of misreporting FEC errors anyway.

Problem: Your upstream sync speed of 1005 kbit is 81% of the average of 1239 kbit for connections with the same upstream attenuation of 16.5dB.

thanks for the info, those stats were taken whilst my router was plugged into the test socket and so i don;t believe my sky box is currently connected, also last time an engineer came i asked him to remove all the extension wires from the master socket so i could eliminate that factor, so i;m pretty sure my sky box is never been connected to a phone line, slap on the wrist from sky. as far as my noise margin i know o2 put it high but i think they need put it on this for 24 hours with a line test before they will authorize a engineer to come out, its very frustrating being treated like a new problem customer by o2 when u have a ongoing issues and a case ref number, every time i ring up they make me go through the basic troubleshooting steps and make me wait 24 hours before referring me to open reach, currently getting 8.78mb down and 0.74mb up, according to a speed test site, speed has never really been the issue as apposed to having a connection that doesn't drop out mid way through a game of call of duty!

my current router stats
DSL Connection

Link Information

Uptime: 0 days, 12:41:01
DSL Type: G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]: 1,005 / 10,167
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.0 / 19.0
Line Attenuation (Up/Down) [dB]: 16.5 / 31.0
SN Margin (Up/Down) [dB]: 16.0 / 15.5
Vendor ID (Local/Remote): TMMB / BDCM
Loss of Framing (Local/Remote): 1 / 0
Loss of Signal (Local/Remote): 1 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 1 / 0
FEC Errors (Up/Down): 5 / 46,299
CRC Errors (Up/Down): 5 / 58
HEC Errors (Up/Down): 14 / 46

Hi. I'm on O2 LLU with almost the same attenuation as yourself. Have you tried monitoring your SNM with DMT or Routerstats as this may possibly help identify the noise source/type?

This is what my connection looks like from the test socket: dmt201003172303.png

At 29.5 dB attenuation, interleaving and a 6 dB SNR with a perfect line it should be possible to sync at 16,000 adsl.tin2tin.net/adslgraphics

Towards the end of this thread (Radio interference), there is an interesting discussion on MW radio interference.

Anyway, good luck with trying to find the cause of your issue