My connection keeps dropping off today and i realised that my wireless light is dropping most of the time ( the wireless light is blue but suddenly disappeared and came back on immediately again)
I use BT home hub 3 as well
John's probably right, but does the hubs wireless light 'flicker' when smart wifi fires in?
To check I'd manually set the wireless channel and then see if it still goes out.
Leave it there and see how it goes
(report back in a few days with any news, unless it drops out again)