I have a Hub 3.0. The ethernet connections from my hub to my devices are perfect, although the speeds are a little lower than usual for this time of day (23.5mbps download compared to a usually solid 50mbps). However, the real issue here is the wifi, which has randomly stopped working.
It is intermittently showing up on my previously connected devices for 30 seconds or so (but with the message "failed to obtain IP address"), before disappearing again. During this time the wifi light on the router remains off. During one of these brief connections, I was able to change the IP address to static and managed to connect one of my devices to the router without it regularly disconnecting, although now the message is "internet may not be available".
I rebooted my hub a number of times, once leaving it turned off for over an hour, but that didn't solve it.
I looked through the forums and found that similar problems were solved by changing the channel on the router in the advanced settings. I have tried this, and it has not made a difference.
I performed a factory reset on my hub, and am still having this issue.
I'm all out of ideas. This community helped me with an issue once before, I'm hoping you can work your magic and do it again!