Well, that's the safety boat weekend over. Good fun - no casualties.
Turns out I didn't see a 'P' on the screen, and when I looked properly it was 'M1' and 'M2'. I would have sworn I saw a 'P', just goes to show how tiredness can affect one.
Comms worked well, especially after I switched off dual watch.

All these push buttons and tiny icons on a LCD screen. Give me an old fashioned switch, which tells you at a glance whether it's on or off and a bright LED to tell me if I'm transmitting or not. Then I wouldn't have to fish out my reading glasses and hunt for a little black blob on the screen.
Nasher - The radio was purchased last year, so it's still in warranty

. I'll talk to Raymarine and probably send it to them at the end of season. Notwithstanding what I've said above, I still think it's a nice piece of kit.
Thanks all for your input.