Having the same problem as many others Bought the Archer C6 as my Virgin Hub 4  did not do everything I wanted (but it did download at over 1Gb  got speeds of around 1100 Mb to 1200Mb )

Tested the Connection directly with the hub 4 today  I got a download speed of  751 Mb SO working  perfectly

Having put the Hub 4 into Modem Mode and Factory Resetting the Router  checked all suggestions

QOS off

Full Duplex

security off

Parental controls off

Wifi off

using speedtest.net  to test  I get

I know a lot of other people seem to have the same problem if a Gigabit Hub is bought for its Gigabit speed then it should work I hav3e read many posts since registering and cant seem to find a solution that works

I might try it in Access Point Mode to see if that works but will lose features, if nothing can be done then I have bought something capable to do something but does not in real-world conditions I could always install DD-WRT on it see if that works

Please any help would be great as I pay a premium Service to have a Gigabit internet speed