...activate / deactivate the CD AutoPlay?

uses
  Registry;

procedure CDSetAutoPlay(SioNo: Boolean);
var
  Reg: TRegistry;
begin
  try
    Reg := TRegistry.Create;
    Reg.RootKey := HKEY_LOCAL_MACHINE;
    if Reg.KeyExists('Software\Classes\AudioCD\') then
      if Reg.OpenKey('Software\Classes\AudioCD\Shell\', False) then
        if SioNo then Reg.WriteString('', 'play')
        else 
          Reg.WriteString('', '');
  finally
    Reg.Free;
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  {Activate  AutoPlay}
  CDSetAutoPlay(True);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  {Deactivate Autoplay}
  CDSetAutoPlay(False);
end;