Annex M Tones issue

[#1]

I've been trying to narrow down the issue I have with Annex M after it was enabled a week ago.

Sync Speed Before:

2.1    Type    ADSL2+ Annex A
2.2    Status    Up
2.3    Uptime    11 days 21 hours 21 mins 47 secs
2.4    Line Rate (Down / Up)    21167 Kbps / 1259 Kbps
2.5    Noise Margin (Down / Up)    3 dB / 7.8 dB
2.6    Attenuation (Down / Up)    19.5 dB / 10.6 dB
2.7    Power (Down / Up)    18.9 dBm / 12 dBm

Sync Speed After:

2.1    Type    ADSL2+ Annex M US 32
2.2    Status    Up
2.3    Uptime    0 days 1 hours 53 mins 11 secs
2.4    Line Rate (Down / Up)    19759 Kbps / 1331 Kbps
2.5    Noise Margin (Down / Up)    3.1 dB / 7.4 dB
2.6    Attenuation (Down / Up)    19.5 dB / 9.8 dB
2.7    Power (Down / Up)    19.2 dBm / 12.2 dBm

This is using a TG582n running firmware 10.2.5.2.FO

I've tried a different router, Billion Bipac 8800NL, and it's still hitting the limit at 1331Kbps or thereabouts. I've tried 2 different filters, and cables from modem to filter, seeing if any of those could be at fault, no change.

I managed to get the bit loading info off the billion using DMT (see attached), and I've just discovered routerstats which got some more info off the TG582n.

Both as you can see seem to be missing tones 33-59 - the ones used for Annex M.

I've swapped everything I can at my end, I've tested the test socket, anything else at my end that could be at fault, modem configuration possibly ?

Anything else, dslam not configured correctly, something on the line?

[#2]

Annex M is so rare these days I'm surprised Plusnet even supply it, are you on a Plusnet Business ADSL service by any chance? I seem to recall that business customers could order it for better upload speed.

Your stats seem to show Annex M is enabled so I assume the router supports it but there is only a small change to the upload speed. I'm afraid you are going to have trouble if you call support as it's unlikely the first line agents will know anything about it. Hopefully one of the staff on the forum will spot this thread, they should be able to help. As for what is wrong and the missing tones, difficult to say, a modem or DSLAM compatibility or configuration problem perhaps.

[#3]

On a business contract. No fibre, no virgin (well actually it stops next door!), where I am so stuck with trying to get annex M.

I tried to eliminate anything at my end with the various combinations of different routers, cables, filters, test socket and all showed the same issue, which points to an issue at the exchange.

I posted here on the off chance someone else might have had the same issue, that there's simply no bit loading on the annex M tones, the tones get loaded on annex A for downstream, just not on upstream when switching to annex M.

[#4]

@Mav  You seem to have left the original post behind which makes my reply which has been moved look rather odd.

[#5]

@RealAleMadrid

Sorry, hopefully all sorted now