As you requested: What can I do to help? We are yet to find a way to reliably replicate the problem ourselves under lab conditions, so it would be helpful if you can reply to this post answering the questions below (and providing any other detail you might think is useful!)
1. Brief description of the problem, and how it masquerades itself.
What are the symptoms?
First obvious indications are that internet pages take a long time to load, or don’t load at all. A page might partially load within a few to thirty seconds but not completely load for about two or three minutes. Sometimes a page only partially loads and a page-refresh might or might not fix this. Other times the pages load quickly. It’s pot luck. Sometimes switching wifi off and on again fixes things, but again only briefly. On MacBook Pros and iPhones, Apple’s App Store reports it cannot connect.
After a while everything just grinds to a halt and nothing works, even temporarily, any more.
In addition, the Hub One’s 5 GHz wifi password appears to be lost and any connected devices have to re-enter the password. However, entering the correct password (even pasting it in from the router admin setup page where the password was set) doesn’t work — the system reports that the password is incorrect.
It’s possible to connect to the Hub One admin web page using wifi to check settings/make changes; it's not necessary to connect using ethernet.
How frequently does it happen?
About every two or three days. Things run relatively smoothly for a while and then it all jams up again.
2. Do the devices having problems appear to be connected or associated with the hub?
Yes, the problem devices are connected by wifi, either directly to the Hub One or indirectly via an Apple Airport Time Capsule which has wifi network (2.4 GHz or 5 GHz) and which is connected to the Hub One by ethernet. This is primarily used to backup MacBook Pros but can also (usually) route internet traffic.
Is the hub status indicator normal/blue when the problem occurs?
The Hub One status light is blue.
3. Do you have the 2.4GHz and 5GHz channels merged (default setting) or split (different wireless network names)?
I have had the channel split. I split them because there were problems with wifi connectivity after we received our Hub One in March and I thought this might fix the problem but in retrospect this seems to have made things worse. I also tried extending the DHCP lease time to 21 days but this made no difference.
If the networks are named differently, does the problem only affect the 5GHz network?
No, it takes dwon my AirPort Time Capsule 2.4 GHz and Hub One 2.4 GHz connections as well.
4. Once the problem occurs is it persistent?
It persists, getting worse over time as described, until the RESTART button is pressed on the Hub One.
Do you have any devices wired to the router and does the problem affect them at the same time?
As well as the aforementioned Airport Time Capsule there are three other directly wired ethernet connections none of which seem to be adversely affected, an Amazon FireTV, a Windows desktop 10 Dell PC and a TP-LINK Powerline adapter which provides distributed connections to various other powerline devices around the house.
5. Are you able to reproduce the problem reliably? Do you think you have a way of triggering it? [for example waking a specific device from power save mode]
No and no.
6. Is the problem always resolved by rebooting the hub?
So far, yes, the RESTART button fixes things. Immediately afterwards everything is back to normal and web pages load as quickly as can be expected, the App Store is available, the internet works as expected.
If so, how long does it take before problems recur?
It recurs after about two or three days, best case scenario after about five days.
7. If specific devices are always impacted when problems occur, please provide details of which devices are impacted and which aren't i.e. manufacturer, model, variant and operating system version.
Apple MacBook Pros from 2009 (El Capitan), 2010 (High Sierra) and 2017 (Mojave), iPhone 8 and iPhone XR (both iOS 13.3.1).
An HP Windows 10 laptop which has no 5 GHz (only 2.4 GHz) wireless doesn’t appear to be affected. It can access internet on the Hub One 2.4 GHz wifi even when other devices can’t. Perhaps this absence of 5 GHz is significant?
8. Have the devices experiencing problems recently received any patches that might correspond with the time the issue first occurred?
No.
9. Please provide a description of your home network setup and all devices in use including whether or not you're using any additional switches, Powerline adapters or wireless access points.
This has already been described above.
Additional information/observations.
I disabled the Hub One 5 GHz option using the advice given on this forum then restarted the Hub One.
Things looked okay initially, although soon afterwards I got stressful error messages saying the passwords for the 2.4 GHz wifi as well as for both Airport Time Capsule wifi networks were all incorrect despite having worked earlier. Switching away from each wifi network seemed to have got rid of this problem. Fingers crossed.
So, in summary it looks to me as if devices that have 5 GHz wifi options get problems on a 5 GHz enabled Hub One, even if they’re not actually using the 5 GHz wifi, whereas devices that don’t have that option, for example wired only or older 2.4 GHz only devices, escape from this quagmire.
