Hi @gg30340
Thanks for your advice about a full hub reset. I had been waiting for the right time to perform this actio, knowing I may encounter complaints from Wi-Fi users (wife and child). I had also been round to several devices to force them to use Wi-Fi instead of hard wire as a temporary step. This worked fine, until everyone wanted to stream 4k video at the same time!
Anyway, as a result of my procratination, a miracle has happened - it started working on it's own. I am doing further checks but all devices that were previously on the wired network are now connected again. I am 100% that neither me or anyone else would have changed the wiring since it stopped working until it now works again. This is very frustrating not to know why it stopped in the first place. But I wanted to post this message as possible solution for others - just wait a few days and see if it resovles itself!
