Slow fibre?

[#1]

I live right around the corner from the green box and the engineer said he got 80 mb/s when he was testing. I'm on 76 fibre.
However I'm only getting 37mb/s wired at best and my "current line speed" is only at 40 mb/s.
What's wrong?

[#2]

Did you sign up for the 80Mb or 40Mb package from PlusNet?

[#3]

Unlimited Fibre Extra witch is 76Mb\s

[#4]

Anybody?