Unity plays only a few gameobject's sound

I'm developing a 2D game, and have a Button prefab what plays a sound when clicked.

I have multiple instance of this prefab on my scene, but only 2 of them plays the sound, the others don't play anything, or just a very short something.

I thought that it is caused by the distance of the camera and the gameObject, but if I place a button what is silent, to the position of a working button, it still won't play anything.

My code is simple:

 ...
 public AudioSource myAudioSrc;
 
 public AudioClip btnSound;
 ...
 protected virtual void OnMouseUpAsButton() {
     if(!isEnabled) { return; }
     myRenderer.sprite       = normalImg;
     transform.localScale    = normalSize;
 
     myAudioSrc.PlayOneShot(btnSound);
     Debug.Log(gameObject.name);
 
     //üzenet küldése az objektumnak a message metódus hívására az data paraméterrel
     target.SendMessage(message, data);
 }
 ...

EDIT:

I've got this working with the code:

 AudioSource.PlayClipAtPoint(btnSnd, Camera.main.transform.position);

So it has to do something with the distances.

Is there any better solution?