How do I stop playing the MediaPlayerElement after moving to another frame?

MediaPlayerElement plays audio after transition to another frame. If I go to this frame again, I can hear two instances of audio: "One" is from the audio of the currently playing video, and the other is from the last time I went to this frame. How do I stop the MediaPlayerElement after moving to another frame?

Reference:

All the code for my XAML part of the frame

<Page.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="/Styles/MediaPlayerDictionary.xaml"/>
        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>
</Page.Resources>
<Grid Background="Transparent">
    <MediaPlayerElement  Name="YoutubePlayer" MaxWidth="640" MaxHeight="360" AreTransportControlsEnabled="True">
        <MediaPlayerElement.TransportControls>
            <video:CustomMediaTransportControls x:Name="CustomMediaControl" IsSkipBackwardButtonVisible="True" IsSkipForwardButtonVisible="True" IsSkipBackwardEnabled="True" IsSkipForwardEnabled="True" IsFullWindowButtonVisible="True" IsFullWindowEnabled="True" QualityChanged="CustomMediaControl_QualityChangedAsync"/>
        </MediaPlayerElement.TransportControls>
    </MediaPlayerElement>
</Grid>

      

        
        
        
      

    

All the code of my C # part of the frame

public sealed partial class VideosPage : Page
{

public VideosPage()
{
    this.InitializeComponent();
}

protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
    base.OnNavigatingFrom(e);
    YoutubePlayer.MediaPlayer.Dispose();
}

public async Task setVideoSourceAsync(YouTubeQuality videoQuality)
{

    try
    {
        var youtubeUrl = await YouTube.GetVideoUriAsync("QTYVJhy04rs", YouTubeQuality.Quality144P, videoQuality);
        YoutubePlayer.Source = MediaSource.CreateFromUri(youtubeUrl.Uri);
        YoutubePlayer.AutoPlay = true;
    }
    catch (Exception e)
    {
        //await setVideoSourceAsync();
    }
}

private async void Page_LoadedAsync(object sender, RoutedEventArgs e)
{
    if (ApplicationView.GetForCurrentView().IsViewModeSupported(ApplicationViewMode.CompactOverlay))
    {
        CustomMediaControl.IsCompactOverlayButtonVisible = true;
    }
    await setVideoSourceAsync(YouTubeQuality.Quality360P);
}

private async void CustomMediaControl_QualityChangedAsync(object sender, QualityChangedEventArgs e)
{
    await setVideoSourceAsync(e.NewQuality);
}
}