Thanks
The BT Hub is rebooored after everything I do, eg most recently after I switched off Smart Setup. The Hub is functioning perfectly, its lights are fine and the event log shows me the broadband connection is uninterrupted.
Whichever port/cable I plug the Humax into is the port that goes up & down. When I first identified the problem the Humax was plugged into port 2. I switched the cable plugged in to the Apple TV (and port 3) and plugged that cable into the Humax Port 2, same cable, and Apple TV are all fine. But port 3 and the Humax drop like a yoyo.
As the event log shows, it’s only the Humax that is dropping the connection. If it was either the port or the cable, Apple TV should now be dropping and the Humax stable.
The issue seems to lie with the Humax box.