We have the newest BT homehub 3.0 i think.
This problem has persisted since we have had the hub.
The Homehub is connected to the internet 24/7, it is never down and gets regular updates. Except the annoying this is that even though it says we are connected to the internet, it keeps disconnecting all wireless and wired devices randomly.
Whilst writing this post the internet on my laptop has disconnected several times but the internet connection to my xbox has not.
Why does this keep randomly happening?
Having previous bad experience I have tried a few things BT normally get you to do like, change the internet channel and turn off/on the homehub and reset it so it can update but with no luck.
How is the xbox connected to the home hub?
There is some help regarding wireless issues here
Its more likely due to mixed wireless speed devices, try selecting wireless b/g only as suggested above.
we have had the hub over a year at a guess.
the xbox is connected through internet wall plugs, everything else is connected wirelessly, iphone, ipad, laptop another xbox wirelessly.
I have changed to b/g only, now will just have to wait and see.