At the meeting last Thursday I raised the problem above and the resolution that Apple had provided. Apologies for the delay in posting this item but I had deleted the Apple supplied link and the related document read out at the meeting did not display the full address. Thankfully I have tracked down the link at the BT website. The issue detailed may also affect other manufacturers devices: -

http://bt.custhelp.com/app/answers/detail/a_id/44798/kw/Dual%20band%20di...

Mike A.