That looks like 40/10 to me something is amiss.

Speak to the ISP, you've been dropped to 40/10 by the looks of this sync figures. I doubt that's DLM banding with both down/up being banded at exactly the 40/10 package limits.

+1 to the 40/10 downgrade

In reply to a post by j0hn83:

Speak to the ISP, you've been dropped to 40/10 by the looks of this sync figures. I doubt that's DLM banding with both down/up being banded at exactly the 40/10 package limits.

My ISP had confirmed with Openreach that the line is set to an 80/20 profile the last time it derated.

When the SFI engineer came round in the week he did say that the line seemed to be reverting to 40/10 despite being set to 80/20 and that he really wasn't sure why, he'd never seen anything like it.

DLM reset did fix it for about 12 hours before it went back to 40/10 again.

Sounds like we need another engineer back out.

Edited by Toonshorty (Thu 13-Apr-17 22:46:30)

Apart from the 40/10 banding or down grade.

With a 16.3 dB attenuation you should be looking at a Max Attainable figure of mid to hi 70's. and maybe even just into te 80s. My line is around 16dB and am currently sync'd at 79.7 so anywhere from say 72 to 82 would be reasonable but at 56.8 something must be pulling it down and the only possibility is noise.


Get MyDSLStats running and make them data available online - others can then view the graphs and comment

.

Could be a faulty port. Have you had a lift and shift?

Agreed, or that rarest of faults, a rectified split pair (VERY unlikely)

In reply to a post by MHC:

Apart from the 40/10 banding or down grade.

With a 16.3 dB attenuation you should be looking at a Max Attainable figure of mid to hi 70's. and maybe even just into te 80s. My line is around 16dB and am currently sync'd at 79.7 so anywhere from say 72 to 82 would be reasonable but at 56.8 something must be pulling it down and the only possibility is noise.


Get MyDSLStats running and make them data available online - others can then view the graphs and comment

.

I've got my brother to setup MyDSLStats, I've no idea how to get a sharing URL for MyDSLStats but his username is Hanayou.

Have had a quick glance ...

Have a look at your Bits per tone graph and tell me if you think there is a problem?

Then look at SNR/tone and Down3 is showing 16dB or so at tone 28 dropping to zero at 2950 ... I would expect something nearer 25 dB dropping to around 5 to 20 at tone 4000

Hlog - atten per tone looks fine and almost mimics mine.

I'm away, so can't look properly, but the key here looks to be in the Quiet Line (QLN) graph.

That shows a lot of noise being picked up in D3 - more than other parts of the spectrum. Normally, D3 is about as noisy as D2 or less, not more.

That explains why SNR per tone is lower in D3 than normal, and therefore why bits per tone is lower there.

Could that mean Zarjaz is right on the split pair? Would that fail to reject noise in D3 more than lower frequencies?