I got my line changed because I was going through a high level complaint, I need to speak to them again because my bras is only 2500 currently so I will ask to have my line retrained and interleaving turned off now I am on the new line, I just dropped the Target noise to minimum (I didn

OK, you're now only 32kbps away from maximum sync. This may well be caused by interleaving being 'on'.
Your current sync will put you on a 7Mbps BRAS profile, within 3-4 days (how long it takes to catch up with increased sync speeds).
If you manage to get BT to understand what you mean by "please turn off and disable interleaving on my line", you may well get the maximum 8128kbps (which will give you a BRAS profile of 7.15Mbps).

It's up to you if you want to go through the hassle of getting your line retrained (or, at the very least, having your target noise margin lowered to 6db), neither of which may ever happen (despite what your ISP says).
The only thing you'll gain by having interleaving turned off, and your line retrained, is a theoretical extra speed of 150kbps (about 2% speed boost), and the knowledge you don't have to keep checking your sync speed and noise margin (in case your router should reboot and lose the changes).

If you do approach your ISP, and manage to get your line retrained (so you can still get full speed, with your router set back to "default" target), let us know (as you'll be one of the first to get it done manually).

There's also talk of an automatic process which gradually lowers your target margin, but this seems to take blocks of 14 days continuous sync (without any drop outs), and requires you to resync after the 14 days, to take advantage.
I've only ever seen one post, by one user, who states this has happened.

The main reason I am going to press for the retrain is if I put my phone number into the wholesale website it tells me I can only get a 1meg connection and 1.5 on max, now I am not sure if the retraining will sort that out but I am worried if I don

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The main reason I am going to press for the retrain is if I put my phone number into the wholesale website it tells me I can only get a 1meg connection and 1.5 on max

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I guess something is very wrong if you get that kind of estimate with an attenuation of only 23 dB!

Until the line was repaired last week I was getting 43

Retrain will not fix the 1.5Mbps estimate.
This is a fault in the BT wholesale database which, unless I'm mistaken, has no physical (or software) link to the ADSL line training process.
I have no idea how to get it fixed, although I think it's important to fix it, as the poor speed estimate may prevent you from migrating to certain ISPs that take not of it (e.g. AOL), and may prevent you from going LLU, to Bulldog, or BE, etc. (as LLU providers use the estimate to decide whether to offer you high speed services).

I'm in the same position. The BT checker says I can get 512kbps fixed speed (even though I had 1Mbps before upgrading to max), and a maximum speed of 1.5Mbps on ADSLmax (even though I'm currently sync'd at 2944kbps, and could sync around 4000kbps before this 15db nonsense started).
Although my line will support 3-4Mbps, I cannot get AOL, Bulldog, BE, or any other LLU, because the BT checker says my line is only able to support 1.5Mbps.

Anyone else reading this have the slightest idea how to get BT to correct the database, with actual measured values (rather than estimated ones, based on postcode or line length)?
Another thing, I don't believe my reported line length of 6.94km. This seems far too long for a 57db attenuation, and far too long for me to be getting 3-4Mbps with a noise margin of 6db. How to get this corrected, also?

When I fist signed up I was getting about 5.5 meg about a month ago something happened and I started getting 2 meg with a bras of 100k, at that point the checker speed went to 1.5 meg and minimum fault speed had gone down to 1.2 meg I was told that this could be caused by the training on the line saying that

Edited by miller75 (Sun 01-Oct-06 20:49:42)

As your postcode gives you a higher speed estimate, it looks like your data is based on measured values (from the faulty line). This really needs updating with good data (best of luck).
Although you can get your line running at the highest speed, by tweaking your own router, the main reason for wanting a retrain, is to correct the stupidly low fault threshold. In your case, caused by a faulty line, in my case caused by rubbish internal wiring.

If you can convince your ISP (BT retail, I believe) to push the appropriate requests to BT wholesale, go for it. You've very little to lose!

I will speak to them and let you know if I have any success

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Edit: To clarify 'SNR'. It is a ratio between signal level and noise level (both being expressed in db). As it's a ratio, it has no unit.

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It's important to stress that SNR measured in dB is a power measurement, and is not linear. So a 3dB increase is double the power, and a 6dB increase is 4x the original power.