there are some predefined sounds: SHUTTER_CLICK, FOCUS_COMPLETE, START_VIDEO_RECORDING, STOP_VIDEO_RECORDING.
Nice!
MediaActionSound
A class for producing sounds that match those produced by various actions taken by the media and camera APIs. Docs
use like:
fun playBeepSound() {
val sound = MediaActionSound()
sound.play(MediaActionSound.START_VIDEO_RECORDING)
}