Thanks everyone for your suggestions.

Being on with Eclipse Technical Support and they were seeing a lot of downstream errors hence the high SNR. After changing filters and connecting an old router we now see a lot of upstream errors. To make things more confusing the same thing happens when I put the previous equipment back (still get upsteam errors).

So Eclipse have put the line back into training mode - hopefully with the downstream errors gone I will get a better connection. Not overally happy with my Master socket as the previous owner put a extension in which at some point must have broken as I now have to permanently use the test socket hopefully that's nothing to do with it.