Had a temporary outage earlier when the connection died completely. Hub 3 is in modem mode. Rebooted the hub and attached network gear. Connection is up again but upload speed is awful. Have not tested with a wired connection but have tested with 2 different wifi connected devices . Even when stood next to the main router with my phone, it struggles to hit 3Mbps upload. Failing to get above 0.5Mbps in other areas of the house. It is usually way higher.
test with the hub in router mode and post some info
log into hub3 - 192.168.0.1 [or 192.168.100.1 if in modem mode] - DON'T SIGN IN, click - click router status [centre of screen] - and post the downstream and upstream figures - to see those press on the grey buttons/boxes labelled - upstream - downstream
upstream channels are all 16qam they should be 64 so try a reboot and see if they change - if that does not help do a reset - hold the button a good 30sec and then some - be aware that will reset all settings back to default - again see if that helps - if not you need some info from staff here - you had an outage the fault if it was that could still be ongoing