can't get Wifi help!

[felface]

So in my house there is sonos and when the person came round they installed a time capsule which when i told my mum and dad what it was we discovered what a bonus we'd been given so our house round coverage of wi-fi greatly increased but recently we've had problems with it and the sonos guy set a password on it without bothering to tell anybody what it is so i did soft reset and changed the password and did everything that it said including stuff with DNS servers and updating the firmware and when after about half an hour it said all was good and the was green for the first time in weeks i thought our coverage would be great but it's actually gotten worse mum and dad are complaining how they can;t get wi-fi in the kitchen anymore when it is no more than several metres of air between them so can anybody think whats gone wrong have overlooked something really obvious ad stupid? thank if you read all of this and even bigger thanks for trying to help

 

[pkcable]

Did you move your router at all? Try adjusting the antennas.

 

[felface]

our router is BT homehub so it doesn't have any atennas but one of the problems was the timcapsule saying that it couldn't connect the network but now it says 'average' so again says all god but actually far from it