If I choose a channel that is currently not broadcasting a signal e.g. BBC Three or Four which are only post 7pm NPVR locks up with a black screen. By locks up I mean I cannot select another channel and have to press stop to get back to the menu. I've just noticed that if I press a number for a channel that is broadcasting the channel will appear after 10 seconds or so sometimes.
UK Freeview HD via WinTV-dualHD on Windows 10 Home 64