Probably only if one of the mods pick up on your post but hey! it's a freefone number and much quicker than waiting for a mod to reply then you have to fill in a form etc etc.
Is it possible to do it online?
No, you will have to report a fault. They will get you to carry out tests to ensure that the hub is faulty and only if it is will they then send a new one out to you. If you are still in contract this will be free but if your contract is ended you will either have to pay for a new one or re-contract.
then phone CS using number already posted
Yeah I'm still in contract with them. Personally I think that my hub got damaged in transit like in the post so I need a new one.
So how come in your first post you said "mine has just broken and instantly I can tell that the signal has gone down dramatically and the wireless isn't as strong".
If it was broken in the post I would have expected it to be like that from the start.
As said, you will need to report a fault. They don't just hand out new ones because the customer says it broken, they need to test it.