Welcome,
Take a look at the FAQ to understand the general audio coexistence issues: https://www.politepix.com/openears/support
OpenEars has audio session settings that it requires in order to function, so it will always reassert them when listening is started. This may also change the play button behavior as a side effect. AVAudioPlayers ought to work more or less as expected if started and stopped inside of the started OEPocketsphinxController session, though.
I don’t quite understand this, maybe I can help more once I do:
I’m listening to a audio button press (i.e. headphone buttons) to activate startListening(). I’d like my own sound to continue after startListening() has begun, so that I can receive when the second button press has happened so that I know to stop the listening session.
What is the relationship between these button presses and listening? Don’t you want to respond to their touch callbacks rather than their sounds?