About sound distortion

Hi! I added walking sound effect to my character and in play mode, the sound is distorted when my character is walking. Does anybody know how to fix it? I have already turned Doppler Factor and Doppler Level to 0 but it didnt work.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class movingcharacterscript : MonoBehaviour
 {
     public float speed = 0f;
     public float rotspeed=80;
     public float rot = 0f;
     Vector3 movDir = Vector3.zero;
     float gravity = 20.0f;
     
     CharacterController controller;
     Animator anim;
     AudioSource m_AudioSource;
     bool AnimPa;
 
     public AudioClip impact;
 
     // Start is called before the first frame update
     void Start()
     {
          m_AudioSource = GetComponent<AudioSource>();
         controller = GetComponent<CharacterController>();
         anim = GetComponent<Animator>();
       
            }
 
     // Update is called once per frame
     void Update()
     {
        
         if (Input.GetKey(KeyCode.W))
         {
             anim.SetBool("AnimPa",true);
             movDir = new Vector3(0, 0, 1);
             movDir *= speed;
             movDir = transform.TransformDirection(movDir);
             m_AudioSource.PlayOneShot(impact, 0.5f);
         }
        
         else
         {
             anim.SetBool("AnimPa",false);
             movDir = new Vector3(0, 0, 0);
             m_AudioSource.Stop();
 
         }
     
        
            
          
       
         rot += Input.GetAxis("Horizontal") * rotspeed * Time.deltaTime;
         transform.eulerAngles = new Vector3(0, rot, 0);
 
         movDir.y -= gravity * Time.deltaTime;
     }
        
      
     }
 
 

@ernest326648 I tried use playoneshot but this time no sound at all.