[Privileged]Decrease the audio output level of a given audio device during voice calls.
#include <audio/audio_manager_volume.h>
int audio_manager_decrease_voice_output_level(audio_manager_device_t dev)
The audio device that the decrease is applied to
The audio_manager_decrease_voice_output_level() function decreases the audio output level of a given audio device during voice calls. The step of the output level decrease is defined by the particular audio device.
EOK upon success, negative errno upon failure