RB751U-2HnD / BT Infinity

Anybody successfully got an RB751 working with BT Infinity with the full download and upload speed?

I’ve been trying on and off for the past 3 months to get this to successfully work without any joy. I’ve just upgraded to routeros 6.6 and that has fixed the problem with it dropping the connection after 5 minutes but there is still the problem with the speed been capped at 10Mbps down and up. I should have 70Mbps down and 20 Mbps up. I think there is a auto sensing issue between the RB751 and the BT Infinity modem.

I’ve tried the work around that was suggested several months ago by putting a 10/100 switch in between the router and the BT modem. This does work but it makes it a messy setup.

I’m new to Mikrotik and routeros so any suggestions are much appreciated.