Audio Source Selection in DVSwitch Mobile


On Page 17 of the DVSwitch Mobile Installation and Setup Documentation Revised 02/17/2020, there is a picture of the screen showing the ability to choose the Audio Source.  This seems to have vanished on my implementation. I am using a Samsung Galaxy A13 running Android 12.  Is there a way of unlocking this, as I would like to operate on "speaker".
Many thanks,
Keith G4WQB