@pepe_fr said in COM/NAV issues:
Another strange thing (was unable to replicate in flight, but on ground only, very strange) : COM radios are OFF when the NAV radios are OFF (ATC dialog is being "grayed").
That's unfortunately a limitation of the way MSFS simulates radios. We have separate power circuits and logic for the COM and NAV radios but, presumably because the default aircraft haven't required entirely separate COM and NAV radios, the two are somehow linked 'behind the scenes'. We've not yet been able to find a way around that.