Ames~
When Enable Spatialization is ticked, if a player causes an audiosource to call audiosource.play() and then moves out of the range of the audiosource and the audiosource is played again, the player will hear the audio for a split second. The audio will then "move" towards its actual location with each successive play of the audiosource until it cannot be heard, as intended.
To reproduce this:
  1. create an audio source and add an audioClip in unity, add the vrc spatial audio source component
  2. check "Enable Spatialization"
  3. Set Spatial Blend to 3D ( and ensure its not global, eg. a custom rolloff)
  4. Add a script that will play the audio source such as:
using UdonSharp;
using UnityEngine;
using VRC.SDKBase;
using VRC.Udon;
public class audiotester : UdonSharpBehaviour
{
[SerializeField] private AudioSource audioSource
private void Update()
{
if (Input.GetKeyDown(KeyCode.F)) audioSource.Play();
}
}
  1. Wire up the audio source game object with a game object that contains the script in the inspector
  2. Put the audiosource game object at 0,0,0 position
  3. Publish the World
  4. In the world in vrchat press "F" once to hear the audio
  5. Move out of range of the audio source
  6. Press "F" again
  7. The start of the audiosource will play at volume for a second, and be heard outside of its defined range