So had this problem today.
Box was in 'Fast Start' standby and was recording to start with.
Using the BT remote - the box would go in and out of standby. And channel up/down was working as well as channel changes using direct number entry.
But pressing home or guide etc. would produce no on-screen graphics at all.
Even when the channels change there was no graphics appearing.
A mains reboot was needed to restore functionality
