An exact sync of 35000kbps and noise margin around 8.6dB suggests your line is banded (capped) by DLM.
With that noise margin your line should get nearer 40Mb.

What modem are you using and are there any more detailed stats?

Hang on, are you saying your modem is normally connected with unfiltered extension wiring connected ?

This would imply a bridge tap, and will ultimately be affecting your service.

In reply to a post by Rex_Luscus:

From nemeth's helpful post (for which, many thanks) it seems I'd be better off downgrading to 40/10 or 55/10 - just hope there's capacity left if/when I switch.

The capacity issue concerns availability of a port on the DSLAM. All variants of FTTC are served from the same ports. Since you already have FTTC you already have a port and migrating is not going to require a change of port. In fact it shouldn't even require an engineer to visit your cabinet. It's even conceivable given your current connection that it can be done without the modem needing to resync.

As long as you migrate and don't cancel your existing service you need have no concerns on that score.

Same where I used to live. The lines were 350m long with about 120m Al segment in them and one synced at 54 Mbps (80/20) and the other at 32 Mbps (40/10).

Morning Zarjax

Where is Aluminium phone wiring mainly -

Is it in the E-sides with its generally Multi-Core cable pairs

or

Or is it on the D-Sides with generally low quantities of pairs?

The adding of extra speed suggests there is a high chance the DLM systems have seen errors and slowed you down, so moving to optimal wiring and leaving there for a few weeks may see DLM relent a bit and give back some speed.

Morning Eckiedox

Can be either, but since the OP is talking about FTTC the E side shouldn't really come into it.

As others have said you are likely banded with those stats, EXACTLY 35000kbps is unlikely to be chance.

What that means is that DLM has decided your line is unstable, and applied a maximum sync rate. This is also why your noise margins are over 8dB rather than the more normal 6dB.

You mention you get better speeds by using the test socket, but I think you are meaning you get better speedtest results? The issue is that it will take days/weeks/months for anything to change when you make a line improvement unless a BT engineer resets DLM, but we would see an immediate difference in stats if you did this and then showed us the stats.

If you could do this, it might help, because it may be that your line is capable of 40m+ if you resolve wiring issues.

It might be worth exploring that before you switch to a 40/10 or 55/10 product, but on the face of it yes, you would be better off downgrading to one of those two if you can get a good deal from an ISP that will give you a decent service (not always best to just go with the cheapest).

Thanks, Zarjaz.

Yes, I had overlooked that being FTTC, the E-side would not be involved.

But worth being aware that it occurs both sides.

In reply to a post by MHC:

If you move to a supplier that still offers 38/2 (if any do)

Plusnet - at least, this was the case two years ago.

I bargained with them and they gave me the "up to 76" service for the same price as "up to 38"; this allowed me to get a 5Mbps upload instead of being limited to 2Mbps.