final sound = SoLoud.instance.load('path/to/sound.mp3');
final handle = SoLoud.instance.play3d(sound, 0, 0, 0);
double xPos = 0;
// set the sound to be inaudible if it's more than 10 units away
SoLoud.instance.set3dSourceMinMaxDistance(handle, 0, 10);
// set the attenuation to `LINEAR_DISTANCE` and when its position
// is 10 units away, the volume will be 0 (inaudible).
SoLoud.instance.set3dSourceAttenuation(handle, 2, 1);
// if the sound is inaudible, it will be killed and the [handle]
// becomes invalid.
SoLoud.instance.setInaudibleBehavior(handle, false, true);
// here we shift the sound position away (up to you to cancel the Timer!)
// When [xPos] reaches 10 units, the [handle] will stop.
Timer.periodic(
  const Duration(milliseconds: 100),
  (timer) {
      SoLoud.instance
          .set3dSourcePosition(handle, xPos += 0.1, 0, 0);
  },
);