Hi Chris
Sadly engineer never showed up. Then had a torrid time on the phone to two customer service reps who were no help whatsoever, in fact second one was quite rude and cut me off.
Out of curiosity and desperation I tried the hub again and it came on !! Not sure if it had just got too hot or what. Don't know what else would have caused it to go down with no lights on whatsoever in your experience.
Regards