Audio is cut in script

I have an Audio Source component attached to my object. I copied the script from here link text

 using UnityEngine;
 using System.Collections;
 
 [RequireComponent(typeof(AudioSource))]
 public class ExampleClass : MonoBehaviour
 {
     public AudioClip impact;
     AudioSource audio;
 
     void Start()
     {
         audio = GetComponent<AudioSource>();
     }
 
     public void play_sound()
     {
         audio.PlayOneShot(impact, 0.7F);
     }
 }

audio is cut in my script

why is this happening?