I have had Infinity and a Hub 5 for a few weeks, all OK until last night when access to the Hub Manager (192.168.1.254) failed, browser eventually times out and reports “Unable to connect server, not responding”.
I can ping 192.168.1.254 and get a response. Everything else is still working fine. Throughput is fine, circa 58Mbits downstream and 19Mbits upstream. Have tried multiple clients (wired and wireless) and a power reset to the hub itself but no joy.
I’m reluctant to try a factory reset because I don't want to lose my configuration settings, particularly if I can't than access the Hub Manager to restore that.
If that doesn't work you will probably need to to a factory reset.
As you have said, you will lose any settings you had but once you have restored them you should make a back of your settings via the Hun Management Settings so that should you need to do a factory reset in the future you can restore your settings from the back up.
You could try removing the adsl cable from the back of the hub, then power down with the power button, give it 10 seconds or so, power back up with the power button. Wait until the routrer is fully powered up, then try and reconnect to it, to get to the management pages before replugging in the adsl cable. However, I would not do this often as we wouldn't want the DLM to kick in.