Oh dear!! Looks like I will have to eat humble pie and apologise to all at BT, I've found the problem. I have a rather complicated wired network through the house, so I decided to check all the cables, and you guessed it I have a faulty cable! it has worked ok for the last 6 years or so , so I assumed everything was ok at my end. When I installed the cable (its a 15m cable) there was some minor damage to the outer insulation right next to the plug, I didn't realise that one of the tiny cables inside was only hanging by a thread, and for some unexplicable reason after all this time it decided to part! I never touched it so inexplicable. This would appear to be the reason for the hub not to work properly as it was shorting to another core in the damage. This could also explain the judder on TV.
So my advice is do check that everything you have is working as it should.
My only gripe now is that the BT Tech guys should have asked me to connect my laptop directly to the hub as this was how I found the fault, and they also suggested the the problem was my firewall.