/// <summary>
        /// Load Playlists
        /// </summary>
        void LoadPlaylists()
        {
            // Load user's playlists
            Task t1 = Task.Factory.StartNew(() => Playlists = PlaylistsSetting.LoadPlaylists());

            // Load application playlist
            Task t2 = Task.Factory.StartNew(() => LoadApplicationPlaylist());

            Task.WaitAll();
        }
        /// <summary>
        /// Save settings
        /// </summary>
        public void Save()
        {
            using (var setting = new PlaylistsSetting())
            {
                setting.Playlists = this.Playlists;
                setting.SavePlaylist();
            }

            Properties.Settings.Default.volume    = Player.Volume;
            Properties.Settings.Default.IsLoopOne = IsLoopOne;
            Properties.Settings.Default.IsShuffle = IsShuffle;

            Properties.Settings.Default.Save();
        }
        /// <summary>
        /// Clean up and refresh database
        /// </summary>
        public static async void CleanDatabase()
        {
            using (var dc = new MusicDBDataContext(Properties.Settings.Default.MusicConnectionString))
            {
                dc.ExecuteCommand("DELETE FROM CHITIETBAIHAT");
                dc.ExecuteCommand("DELETE FROM BAIHAT");
                await Task.Run(() => { dc.ExecuteCommand("DELETE FROM TUA"); });

                await Task.Run(() => { dc.ExecuteCommand("DELETE FROM CASI"); });

                await Task.Run(() => { dc.ExecuteCommand("DELETE FROM ALBUMS"); });

                await Task.Run(() => { dc.ExecuteCommand("DELETE FROM THELOAI"); });

                await Task.Run(() => { PlaylistsSetting.DeletePlaylistsFile(); });

                dc.SubmitChanges();
            }
        }