40000 Kbps before the banding, 33.1 Mbps download and SNR Margin is 10/6 with 0 ES on Downstream.
So just to confirm that's 10db downstream SNR and 6db upstream SNR?
Yes.
Right, well then I recommend you getting in touch with BT tomorrow using the Live Chat in the following link.... http://btsupport.custhelp.com/app/answers/detail/a_id/53505
This link is whats been given to me by BT's Twitter team (@BTcare)... they seem to know a lot more than BT's tech support chat which as you probably would guess seems to be oversea's...
Ask them if they know what SNR is???
When they reply yes ask them if they know what a banded profile is, and go from there and just explain that your SNR is 10db and the connection syncing correctly at 6db will boost your speed back to its previous...
If it comes to it ir it actually was the case, tell them that you had a fault with the router that cause DLM issues and that you would like them to request a line reset from BT Wholesale or Openreach...
Hopefully this works out for you, I seem to be getting more sense out of them at the moment, but then my many tweets to them over the past 3-4 months are not what they would consider good for their public profile and customer service portal.
I decided to give this a go. Surprising enough, it worked! I now have an engineer booked to "check my cabinet" on Tuesday the 19th. I presume the person I spoke to realized that an engineer needs to come to give the go ahead to reset the DLM to remove the banding from my line. Many thanks for the information
Brief background on my connection/issue: I had Sky FTTC for around 2 years, sync'd at 33-34mbit with the usual 6DB SNR, completely stable though heavily interleaved. I moved to BT Infinity option 1 and it decided to apply banding to my connection, restricting my sync to 27400Kbps. Weeks have gone by and no sign of the banding being removed. G.INP was applied to my line recently, which pumped up my max attainable rate to 38mbit. SNR while banded is 10-11DB.
I've attached a screenshot of the live chat, for anyone interested (edited out personal information and the Surname of the agent I spoke with)