#pas
uses ComObj;
...

//процедура открывает плейлист
procedure TMainForm.LoadPlayListClick(Sender: TObject);
var wmplayer, playlist: OLEVariant;
    i: integer;
begin
   case TPopupMenu(Sender).Tag of
    0 : sOpenDialog1.Filter := 'Playlist-asx|*.asx';
    1 : sOpenDialog1.Filter := 'Playlist-pl|*.pl';
    2 : sOpenDialog1.Filter := 'Playlist-pls|*.pls';
    3 : sOpenDialog1.Filter := 'Playlist-wpl|*.wpl';
    4 : sOpenDialog1.Filter := 'Playlist-m3u|*.m3u';
    5 : sOpenDialog1.Filter := 'All playlist|*.asx;*.pl;*.pls;*.wpl;*.m3u';
   end;

  if sOpenDialog1.Execute then
    begin
    if (wosPlay in WaveOut.State) then
      begin
        YesOnWaveStop := False;
        WaveOut.Stop;
        YesOnWaveStop := True;
      end;
     sPlayList.Items.BeginUpdate;
     sPlayList.Clear;
     wmplayer := CreateOleObject('WMPlayer.OCX');
     playlist := wmplayer.CurrentPlaylist;
     playlist := wmplayer.newPlaylist('User', sOpenDialog1.FileName);
     sProgress.MaxValue := playlist.Count-1;
     for i := 0  to playlist.Count-1 do
      with sPlayList.Items.Add do
       begin
         ImageIndex := -1;
         Caption := playlist.Item[i].getItemInfo('Title');
         SubItems.Add(playlist.Item[i].durationString);
         SubItems.Add(playlist.Item[i].getItemInfo('SourceURL'));
         sProgress.Progress := i;
       end;
     sPlayList.Items.EndUpdate;
     ListCount := 0; // обнулим счётчик
     idxStack := 0; // и индекс текущщей композиции
     sProgress.Progress := 0;
     //sProgress.MaxValue := sPlayList.Items.Count; // максимум для прогрессбара
    end
    else exit;
  SelectFile(0);
  Play(0);
  playlist := unassigned;
  wmplayer := unassigned;
  sProgress.MaxValue := sPlayList.Items.Count;
end;