iOS: reroute system sound to earpiece (receiver)? -

iOS: reroute system sound to earpiece (receiver)? -

i'm adding voice memo feature enterprise app. i'm using iphone's proximity detector start recording when user lifts phone face. action uses scheme sound (audiotoolbox) play "beep" sound allow user know it's recording.

my problem beep plays through lower speaker. i'd play through earpiece when user raises phone face, siri does.

since recorder/playback functionality, mixing both systemsound , avaudiosession in same class. know how reroute avaudiosession either earpiece or speaker, can't figure out how systemsounds.

any ideas?

thanks!

ios system audio system-sounds