Just to add to what SonarUK has said ...
Make sure the Asus has been updated with the latest software.
Ensure the ethernet cable from the Asus is plugged into the Hub using the port nearest VM cable entry point.
Whilst in the WAN tab, set DHCP Query Frequency to 'Normal Mode'.
Turn both the hub and the Asus off. Turn the Asus back on and allow it to fully reboot before you turn the hub back on.
********* SuperHub 2ac - Asus rt-ac68u Router - Vivid 100Mbps **********