Line speed halved overnight

My parents recently got moved over to a new infill cabinet last year, which improved speeds from 12/1 to a very respectable 76/20. The line has been running at 76/20 for the past few months without any problems whatsoever, but DLM decided to resync the line overnight a week or so ago.

Since the line resynced, the speed has dropped by over half - with the IP profile falling from 75.68 to 38.67, the upload profile remains at 20 - but actual throughput is around 9Mbps.

Putting our number into the DSL checker shows that a clean line should achieve between 74.2 and 55 Mbps, with an impacted line that falls to 62.9 - 38.8. This puts our new speed at or below the quoted impacted low, when previously we were achieving slightly above the clean high speed.

With the drop as severe as it is, would it be possible to get the DLM reset - or will it be a case of waiting for a few months and hoping it decides to up the sync rate in it's own time?

I'd post line stats but unfortunately BT provided us with an ECI modem, so I can't get the stats.

It is possible a mistake has been made and the line capped to a 38/9.5 product at some point

Its one where the ISP needs to get onto Openreach due to the scale of the drop

Do you have dial tone?

If so can you dial 17070 and run the quiet line test. It should be silent.

If it is, test into the test socket with the router by removing the faceplate from the master socket and retest the speed.

Also if the OP doesn't have a dial tone then one of their wires is broken, that will half the speed.

Paul

I'd second that Mr.S.

Yep, I know, that's why I asked the question

In reply to a post by PaulKirby:

Also if the OP doesn't have a dial tone then one of their wires is broken, that will half the speed.

Paul

That happened to me once, the engineer said vibrations sometimes make one of them come out of the connector in the cabinet, he walked around to it, presumably shoved it back in and bingo everything was fine.

the engineer said vibrations sometimes make one of them come out of the connector in the cabinet,

Used to be the case with the, now rarer, PC100 terminations.

These days it usually 'Edward Scissorhands" the pushed for time contractor who causes it.

Uno have got back to me and confirmed that Openreach report the line as running the following profile:

Profile Name 0.128M-80M Downstream, Error Protection Off - 0.128M-20M Upstream, Error Protection Off

Is error protection G.INP? We currently have an ECI modem on a Huawei cab, so if these modems don't support G.INP then maybe it would be worth sourcing an HG612.

Uno are requesting a frames SFI from OR to investigate further.

I'll also someone to test the phone in an a couple of hours.

"Error protection off" aka "Fastpath" refers to no interleaving on the line whether it is the standard form of interleaving or from G.INP.

If it's G.INP interleaving then it will report "retransmission low/high" in that same section. If its just normal interleaving then it will report "interleaving low/high" etc.

Will definitely be worth looking into a HG612 Version 3B (will have sticker on back saying 3B) if you're sure you on a Huawei cab. Grab firmware B030SP08 from Kitz website and read about unlocking/flashing process. Look to spend around £20-40 for a HG612 modem, not any more.