In reply to a post by chrispurvey:

Your connection certainly looks better than it was but still there are certain issues. I'll speak with our faults team to see if we can get this picked up, It may be worth us setting the SNR target on the DLM higher.

Alternately rather than reducing the speed on an already pretty slow line to cover up the issue we could try figuring out why it worked just fine on Sky at 6dB but is a bit of a nightmare on BT Wholesale at 6dB.

Perhaps deeper INP and interleave would be an option?