AdvGridPDFIO with transformed umlauts

I'm using TMS ComponentPack 8.7 with

TAdvanedStringGrid 8.3.1

When exporting an AdvStringGrid to a Pdf with AdvGridPDFIO, it can happen that umlauts are transformed to "Ö" (insteal of "Ö").
I use TRichEditor as Cell Editor and it seems it happens when I change the font. At least it happens when I change the font to "Arial" or "Microsoft Sans Serif", I didn't try more fonts.

I did various tests and I cannot reproduce this.

Do you use the latest version of the components?

Test code:

procedure TForm1.Button1Click(Sender: TObject);
begin
  advgridpdfio1.Save('e:\tms\temp\specialchars.pdf');
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  advstringgrid1.Options := advstringgrid1.Options + [goEditing];
  AdvStringGrid1.DefaultEditor := edRichEdit;

  advstringgrid1.Cells[1,1] := 'Düsseldorf';
  advstringgrid1.Cells[1,2] := '<b>Köln</b>';
end;

procedure TForm1.SpeedButton1Click(Sender: TObject);
begin
  if fontdialog1.Execute then
  begin
    AdvStringGrid1.InplaceRichEdit.SelAttributes.Name := FontDialog1.Font.Name;
    AdvStringGrid1.InplaceRichEdit.SelAttributes.Size := FontDialog1.Font.Size;
  end;
end;

I changed the font at runtime to various fonts for the selected text with umlauts and I could never see an incorrect character exported.

If a problem persists, please isolate this and provide some sample source application + detailed steps with which we can reproduce this here.