Yes stereo selected, HS button showing and on, headphones set in config.
Again this was working fine then suddenly its not working.
I can see on the screen what I am saying - the FO just doesn't start/respond to flows or checklists.
I spent a great deal of time trying to workaround this - I have read and tried plenty of solutions offered in the forums on the troubleshooting page.
Apart from the simple stuff what else do I need to check?