public async Task CallsAudioPlayerPause() { var audioPlayerCallback = Substitute.For<IMediaPlayerCallback>(); using (Library library = new LibraryBuilder().WithPlaylist().WithAudioPlayer(audioPlayerCallback).Build()) { Song song = Helpers.SetupSongMock(); library.AddSongToPlaylist(song); Guid token = library.LocalAccessControl.RegisterLocalAccessToken(); await library.PlaySongAsync(0, token); await library.PauseSongAsync(token); } audioPlayerCallback.Received(1).PauseAsync(); }