auto-pst-pdf package in combination with textpos and chemmacros

I seem to have problems with the auto-pst-pdf package, chemmacros package and the textpos package.

documentclass{scrbook} 
usepackage[utf8]{inputenc} 
usepackage[T1]{fontenc} 

usepackage{graphicx} 
usepackage{auto-pst-pdf}
%usepackage{chemmacros}
usepackage[absolute]{textpos}

begin{document}
begin{textblock*}{29mm}(45mm,80mm)
    Some random text.
end{textblock*}

end{document}

If i comment out the package chemmacros, my random text is displayed correctly. If I activate the chemmacros package, my text completely disappears as I implemented it into the textblock.
If the auto-pst-pdf package is not used at all, this problem does not occur.

I do not know, why this happens, but I really need all three packages for my thesis. I use Texmaker 5.0.3 on a MacBook running macOS Catalina. Similar problem occurs with TeXShop Version 4.44.

Can anyone help me to solve this problem?

Thank you in advance!

documentclass[a4paper,11pt]{article}

usepackage[utf8]{inputenc}
usepackage[T1]{fontenc}

usepackage{auto-pst-pdf}
usepackage{tcolorbox}

usepackage[absolute,showboxes]{textpos}

begin{document}
begin{textblock*}{7cm}(2cm,2cm)Essaiend{textblock*}
end{document}