Xamarin MediaManager: No sound after installing my application from Google Play Console internal testing

Question

I have no sound when I open my application right after installing it on my Android phone. But when I quit my application and reopen it then the sound works normally.

Why is there no sound when I open the application the very first time on my phone?

I only call CrossMediaManager.Current.Init(this); once in OnCreate located in my Activity1.cs.

 protected override void OnCreate(Bundle bundle)
 {
     base.SetTheme(Resource.Style.MainTheme);
     base.OnCreate(bundle);
     Xamarin.Forms.Forms.Init(this, bundle);
     Xamarin.Essentials.Platform.Init(this, bundle);
     CrossMediaManager.Current.Init(this);

     if (Intent.Extras != null)
     {
         foreach (var key in Intent.Extras.KeySet())
         {
             var value = Intent.Extras.GetString(key);
             Log.Debug(TAG, "Key: {0} Value: {1}", key, value);
         }
     }

     DisplayMetrics displayMetrics = new DisplayMetrics();
     WindowManager.DefaultDisplay.GetRealMetrics(displayMetrics);
     int w1 = displayMetrics.WidthPixels;
     int h1 = displayMetrics.HeightPixels;
     _game = new Game1(w1, h1);
     _game.Run();
}

In addition, I play my songs like this(in another class):

if (Xamarin.Forms.Device.RuntimePlatform == Xamarin.Forms.Device.Android)
{
    string androidfilename = "file:///android_asset/" + songfilename;
    await CrossMediaManager.Current.Play(androidfilename);
}

I use nuget package Plugin.MediaManager (1.1.0).

I created an issue on github: https://github.com/Baseflow/XamarinMediaManager/issues/855