Possible Solution.

On my Pioneer remote, there's a button called "RETURN". On an out-of-the-box receiver, it sets the receiver to FM RADIO in standard audio mode and dis-engages the monitor button. In other words; RETURN appears to always place the receiver into the same settings for FUNCTION and AUDIO MODE; so I have been able to program the PRONTO with a working source and audio mode selections by selecting RETURN, and then toggling to the settings I really wanted.

Hope it helps