I upgraded my BT Infinity 1 to the new 52meg speeds and recontracted as I didn't plan on leaving BT and I was getting around 37Mbps+ I thought its worth it. Since I have been upgraded I am now only getting about 30Mbps, what has gone wrong? I've not moved my HH5 or any of the cables.
Post the stats from troubleshooting then helpdesk
Are you using a modem?
can you run btspeedtester and when first test completes then run diagnostic test and post results.
Upgrading will have caused a DLM reset to be applied to your line and may have removed G.Inp. Give it a few days to see if it gets re-applied.
I have exactly the same issue as you so hoping you find an answer! Will leave it a few days and check again as suggested in Licquorice's post.
You would be better tarting your own thread and post your router stats unless you also use a locked modem
I'm having exactly the same problem. What a joke, no wonder they get us to sign a new contract when 'upgrading'. I Should have stayed with Virgin Media.