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When it starts to become dark around 18:00pm, the router can't use many of the tones, therefore becoming unstable, Also the connection wont work if bit swapping is enabled, as soon as it starts the connection drops, with upstream hec errors going wild, 1000per min. Could this be an affect of cross talk, as it only seems to happen when it becomes dark. Also as can be seen by the QLN graphs there are quite allot of spikes. Neighbors are complaining as their lines are also noisy,but bt turn up and don't fix it, but as we can tell the same fault is affecting all of our line, and playing havoc with broadband.

[JGO]

Increasing cross talk in the evening seems a probable cause, and short of going on shift work, no "fix" I know.

BT can only do a limited amount because it is inherent in their copper pairs culture - supported by bean counters 'cos it costs less than FFTP.  Interleaving and vectoring are supposed to help but you can't "fix" a basic principle of physics with software, only try and make it less obvious. ( I did meet a situation where something similar hid the effect of interference on TV 100% .)

It can also be mitigated by the same means as other local interference, i.e. filter ring wire, decouple from extension wiring and common mode rejection (RF3 etc)   
To avoid it completely means FFTP or satellite - expensive !

[kitz]

>> Also the connection wont work if bit swapping is enabled,

I cant answer why that should be that Im afraid, as bitswapping is supposed to keep a connection more stable. 
 
There is only one possible theory that I can come up with as to why that should be.  When bitswap is enabled during the sync phase a tiny overhead is added in to the snrm calculation somewhere to give headroom for bitswap to occur.  Ive no idea what the margin is, but its supposed to be practically negligible. Turning off bitloading 'may' be giving your SNRm just that miniscule amount of SNR to load a single bit.   But once that line sees any small fluctuations in any SNR, those tones will be unusable and the line far more likely to crap out.

>>> starts to become dark around 18:00pm, the router can't use many of the tones, therefore becoming unstable,
>>> Could this be an affect of cross talk, as it only seems to happen when it becomes dark.

Could be many things. 
More people home, so more general background interference from electrical appliances.
A small amount of EMI/REIN from an appliance which is only switched on during the evening time.
Street lighting used to be a common one.
More crosstalk as more people use their connections.


Most lines will lose SNR in the evenings just due to general background and atmospheric changes its a well known fact.
There was a really good post written on these forums by someone a couple of months ago who explained it in a clear and simplistic way.   I'm afraid I can't recall who and where now.  Perhaps someone else can recall?

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What about the neighbors having a crackly line, although their lines seem to be worse, Although only 2 have adsl, but the ones that have crackly line, sound similar to mine?, So the fault isn't only affecting me? This is what happens with the bitswap, the SNR drops from 5.0db to 0db?, Also when the connection drops the DS error seconds pile in, but the US CRC errors are about 2700per min according to dslstats, and 3600per min DS. The FEC errors for upstream fly to 3000per min, once dropped, but with bitswapping off, its the DS that increase to around 5000per min.

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Also if i ring the neighbours that are further on the line, houses further from the exchange, i can hear the ringing pulses/clicking, Also looking at btwholesales line checker, the speed range has increased from 0.25-2mb to 0.75-2.5mb, So how is this also calculated. But this issue of the noise, has come after the tie pair mod, could it be a faulty line card,which creates noise when it becomes dark?, With symptoms of a hr fault, can hear router sync on line if unplugged, and plugged back in. Bad soldering in exchange?

[kitz]

>>> What about the neighbors having a crackly line, although their lines seem to be worse,

Im not a telco person so not the best person to answer, but its possibly some sort of common fault, although I know not what :/

Its known that REIN can affect several houses, but if the lines are crackling to me that would point to something a bit further down the line or possibly something at the DP?

[burakkucat]

I'm getting confused with the various symptoms being reported. So let's make a start with your line.

• Disconnect the modem/router.
• Remove the lower front face-plate of the NTE5/A.
• Confirm that every other telephone extension socket within your premises is/are now inactive.
• Plug a traditional, wired, telephone into the now exposed "test socket" on the NTE5/A.
• Make a call to 17070 and take Option 2.
• Listen.
• If any crackles, hums, whistles, plops -- i.e. anything but silence -- are heard, report a "noisy telephone line fault" to the entity to whom you pay your line rental. Do not mention broadband when making that report. Wait for the fault to be fixed.

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With an older cable and wireless cwp200, there is a buzzing, which can be heard whilst covering the microphone, but if silence is pressed it dissapears, the buzzing is probably the phone, also have a bt decor 1200, which is relativly quiet, until the very intermittent crackle/rustling. Had one appearance of the whistle. Is the dp the cabinet, as the council had to dig a trench as the cabinet kept getting flooded by the rainwater?

[burakkucat]

The best type of phone to use is a simple, straightforward, classic device without any "features". One that does not require a power supply, etc. I have no knowledge of those two particular telephones that you have mentioned.

The DP (distribution point) will either be at the top of a pole, if your service has an aerial feed or will be in a pavement chamber, if your service is underground fed.

There are many types of cabinets in the average street. Are you sure the one that was flooded is owned by BT?

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Yeah it was definitely the cabinet owned by bt, could it be the water in the cabinet causing the fault?, The previous engineer checked the dp at the top of the pole and said it looked fine?

[burakkucat]

Without looking inside that cabinet, it would be impossible to say. 

To what height would you say it was flooded? Between 2 - 6 inches? Or between 1 - 3 feet?

If you really tug on my tail, I'll suggest that 6 inches or less probably would not be a problem. One foot or more and there could be troubles ahead . . .

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I wouldn't say more that 6-7 inches, but i cant really tell, but the ditch dug, has us running like a stream, so there probably was quite a lot of water, it could explain the possible hr fault, and affecting other line though?, the upstream isn't affected as much, as it was before Christmas, so perhaps water was affecting the line, as the line would drop sometimes if the line was used, but still before the engineering work was done, always had a 21.0db upstream snr, now on a good day 15.0db, but when hr symptoms present 7.0db, with 160kbps upstream speed. Could the hr fault get worse then better?

[burakkucat]

A HR fault can certainly present variable symptoms dependant upon a multitude of factors, yes. Significant water ingress into a PCP could result in faults on any of the lines that transit through the cabinet.

If you have noise on the line -- without any xDSL equipment connected -- then it would be sensible to report it and have it fixed. Do not mention "broadband" when reporting the noise. Keep the report simple and brief.

Until such time as the telephony circuit is operating within specifications, it is just pure speculation as to what may (or may not) be wrong with an xDSL service. 

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After a while selecting different lw, and mw frequencies i have found that the tones that are affected, and the large spikes on the QLN graphs at night are caused by these stations, so there must be a bad joint(hr fault), picking up all of the interference, as the AM frequencies transmit much more easily when dark.But as can be seen by the QLN graph the spikes are much larger at night, but what also doesn't make sense tone 48, at 207khz has an am station on it, but is still the one with the highest snr, but no spike on the qln, the station is patchy, but sounds foreign. Where tone 50 has a spike, but on the frequency 216khz, it sounds like a fierce whistling kettle? But during the day there is a station with pulsing interference.

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Would it be the hr fault picking up the stations, as during night it sounds very faintly on the phone like an AM radio station.