I think I have this NTE5c mk4 master socket which was installed in 2017. We just have a master socket, no extentions.
As I already mentioned I was getting 22mbps to the router on standard broadband.(where theoretical maximum speed is 24mbps). So my line can't be noisy.
Is there a way I can check if my line is noisy?

Noise can come and go as can other customers which affects sync speed. My speed just inexplicably dropped from 80 to 66.

As ADSL2+ is using a different spectrum of frequencies performance on that does that have a linear relationship to performance on VDSL2

i.e. almost max ADSL2+ speeds does not mean you will see almost max VDSL2 speeds

Every line has noise on it - it comes from many many sources almost all of which are outside your control.

Examples: Radio transmissions, cross talk, electric motors, PCs, televisions, traffic lights, central heating, fridge freezers,, and te frequency of the noise will be from DC to light!

Look at any DSLstats bit loading graph and there will be dips where radio transmissions occur - 720 kHz, 909kHz, 1215kHz, 1440 kHz, &c. Other sources may be wideband and may not be as easily noticeable of may have just a small effect - 1 or 2 bits per tone compared to 10, 12 or more for radio transmissions

In reply to a post by Customer69:

i don't know, that could be SNR. I did the noise test on my line and there is no noise. that makes me believe that 6dB is just the level of background noise.

SNR is indeed what is important. That is what determines the maximum possible speed on a line. However it makes no sense to let a line connect at its maximum, as the moment a noise impulse occurred the connection would drop. SNRM(argin) is therefore applied by the system, reducing the sync so that when such extra noise happens it is accommodated in that stability margin.

SNR and SNRM vary together. If the noise increase is greater than the margin set at sync time then the connection will fail, and reconnect at whatever speed it can. Depending on what noise then exists, but with a full margin.

See this page for more detail of how it works.

thanks for your help guys,
It looks like DLM is sort of working. Almost a week into training period DLM finally did something. The noise margin is reduced by 0.1 dB both ways and speed is also reduced.

here are the new DSL stats.

DATA RATE INFORMATION
Upstream 18702 (Kbps)
Downstream 57468 (Kbps)

DEFECT/FAILURE INDICATION
Operation Data Upstream Downstream
Noise Margin 6.1 (dB) 6.2 (dB)
Line Attenuation 0.0 (dB) 14.3 (dB)

In case someones interested in the ping:
ping to google.co.uk:
before training period: 11 - 13 ms
1st day of training period: 19 - 20 ms
5th day of training period: 26 - 27 ms

where ping to 192.168.1.1 was <1ms.

DSl status page on this router hardly shows any info. Does Bright box 2 router support telnet.

That looks a bit as though Interleaving has been applied due to high error rates. On its initial application a latency increase of a minimum of 8ms is usual, with a sync speed reduction of 6-8Mbps.

I should also be getting close to the max. speed but get 62 Mbps or thereabouts.

I am close to my cabinet which is also close to the exchange.

OR has tested and tell me that there is some ally cable somewhere in the system that supplies me and that is why I will never get the full speed. This only showed up when I got the speed boost.

Just a thought but may explain your speeds.

In reply to a post by Customer69:

Almost a week into training period DLM finally did something.

There Is No Training Period!