The radio button on the MFD does not show on occasions.
Ideas
Same. No change to default button bindings for my Logitech G920. Was working initially. Disappeared from screen at start of My Team career mode during practice/qualifying for first race. Have checked bindings, unbound, rebound. It's disappeared entirely. Not just OSD visual prompt, but the radio messages menu fails to launch when the bound button is pressed. Very irritating not being able to communicate with pits.
Also tested in single Grand Prix with the same result.