I recently was migrated from BE to Sky broadband, and completed the initial 10 days 'line training' with the DLM monitoring the line.
During this period my connection speed dropped from my old BE speed of between 3 and 4Mbps with 6db noise margin... to 2.7Mbps and a noise margin of 9db...
I got on to Sky support and after trying various things to get my speed back up to pre Sky speeds... they agreed to turn off the DLM for my line, after which my speed went back up to around 3Mbps and noise margin of 7.5
Although the line is very long to the exchange it is a stable connection always has been.
Can someone please explain why Sky use the DLM which seemed to favour stability over speed on my line. I hope Sky leave the DLM off as there is no problem with noise/stability on my line.