troubleshooting poor fibre download speed

[#1]

under 100 yards from the cabinet, same exchange as prior to my house move, estimated speeds: 80/20 (i.e as good as it gets)
actual speeds: 20mb up/20mb down
open reach engineer has just left, having found no trace of a fault.  i've tried: bypassing my router (straight to the OR modem), he's tried changing the socket face, the network cable, and the modem cable. his gizmo showed no trace of a fault.
so, perfect upload speed, but adsl 2 level down speeds
thoughts, suggestions, things that it could still be?

[#2]

This should be in Broadband and Routers section but check the BT IP profile and see if it matches the PN IP profile, at a guess they don't match
http://speedtest.btwholesale.com/ run that then the further diagnostics test button, the IP profile should roughly match the Current line speed from https://portal.plus.net/my.html?action=data_transfer_speed

[#3]

why should it be in routers? there is nothing wrong with my router
Adam/PN have already looked at the ip profile.
I've done the further diagnostics - it confirms the poor speed that I see, I get as far as far as it wanting me to run the tap3 test, but that test is broken on the btwholesale site (follow the steps, change the router, but DNS resolution is broken and the test cannot run). That is the point that lead to the engineer visit today.  He was puzzled, called his office who also had no idea, then he was gone

[#4]

Quote from: meem

why should it be in routers? there is nothing wrong with my router

Speed issues are usually dealt with in the "Broadband and routers" forum, that's all.
FWIW: I could not get the tap3 test to work either - also suspect a DNS problem.

[#5]

Hi  meem,
The fault has been sent back to us from BTW, I've now rejected the clear to advise them there's still an issue. This will go back to BTW for further testing.
Our faults team should pick this back up again over the next day or two.
Dan

[#6]

he told me that he raised it with another fault team at BTW that didn't work weekends...  disappointed to see that wasn't actually the truth, and they were just washing their hands of it
anything I can do to get this moving?