seeking video by using audioSource.time not working

Hello everyone. Im a beginner in unity scripting. i need help with my script. i want to seek a movietexture by using audiosource. but it is not working as expected. below are the script

 using UnityEngine;
 using System.Collections;
 
 public class PlayAt : MonoBehaviour {
 
     AudioSource audiosrc;
     MovieTexture VideoClip;
 
     void Start () {
         audiosrc = this.renderer.audio;
         VideoClip = (MovieTexture)this.renderer.material.mainTexture;
 
         if(VideoClip.isReadyToPlay)
         {
             //audiosrc = new AudioSource();
             audiosrc.clip = VideoClip.audioClip;
             audiosrc.time = 20f;
             VideoClip.Play();
             audiosrc.Play();
         }
     }
     void Update () {    
     }
 }

thank you for any help..