Currently on the Radius 2.0.0 Sample Application, the following behavior will occur:
Transmitting with Radius SDK
The behavior broadcasting with LISNR Radius while using headphones is the same as if you were listening to music then took a phone call. On mobile platforms, the headphone audio stream/music will be interrupted:
during tone transmission only (Android)
when Radius is in use (iOS) - begins when Radius object is created and ends when Radius object is destroyed/shutdown.
By default the Radius SDK will force tone transmission to occur on the mobile device speaker, not through the headphones. This is expected outcome as the speaker on the mobile device will be more powerful than transmitting the tone through the headphones.
Receiving with Radius SDK
iOS - headphone audio may be paused while receiving tones*
Android - headphone audio is not interrupted while receiving tones*
*Updates to Android OS and iOS may affect this behavior. OS version specific testing is recommended.