Reihenfolge Kurzbelege bei \parencites

\begin{filecontents*}{\jobname.bib}
@incollection{Fruh.1992,
 author = {Früh, Werner},
 title = {Realitätsvermittlung durch Massenmedien. Abbild oder Konstruktion?},
 pages = {71-90},
 publisher = {{VCH Acta humaniora}},
 editor = {Schulz, Winfried},
 booktitle = {Medienwirkungen: Untersuchungen im Schwerpunktprogramm {\dq}Publizistische Medienwirkungen{\dq} (Forschungsbericht)},
 year = {1992},
 address = {Weinheim}
}
@incollection{Weischenberg.1994,
 author = {Weischenberg, Siegfried},
 title = {Journalismus als soziales System},
 pages = {427-454},
 publisher = {{Westdeutscher Verlag}},
 editor = {Merten, Klaus and Schmidt, Siegfried J. and Weischenberg, Siegfried},
 booktitle = {Die Wirklichkeit der Medien},
 year = {1994},
 address = {Opladen}
}
@article{Tuchman.1976,
 author = {Tuchman, Gaye},
 year = {1976},
 title = {Telling Stories},
 pages = {93-97},
 volume = {26},
 number = {4},
 journal = {Journal of Communication}
}
\end{filecontents*}
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage[babel=true,german=quotes]{csquotes} 
\usepackage[style=apa,backend=biber,language=ngerman,apamaxprtauth=99]{biblatex}

\DeclareLanguageMapping{ngerman}{ngerman-apa}
\DeclareFieldFormat{apacase}{#1}

\makeatletter
% Aus: <http://tex.stackexchange.com/a/70183>
% original definition of \cites
\DeclareMultiCiteCommand{\cbx@cites}{\cite}{\multicitedelim}

% new definition
\DeclareMultiCiteCommand{\cites}[\cbx@cite@wrapper\cbx@cites]{\cbx@cite}{}

% first pass saves keys, prenotes, postnotes
\DeclareCiteCommand{\cbx@cite}
  {\csxdef{prenote:\thefield{entrykey}}{\thefield{prenote}}}
  {\listxadd\cbx@savekeys{\thefield{entrykey}}}
  {}
  {\csxdef{postnote:\thefield{entrykey}}{\thefield{postnote}}}

% second pass outputs sorted citation list
\newrobustcmd{\cbx@cite@wrapper}[2]{%
  \def\cbx@savekeys{}%
  \def\cbx@citecall{#1}%
  #2\cbx@sortkeysinit\cbx@citesort\cbx@citecall}

% internal list of saved keys => sorted argument list
\def\cbx@citesort{%
  \def\do##1{%
    \ifinlist{##1}{\cbx@savekeys}
      {\protected@xappto\cbx@citecall{%
         [\csuse{prenote:##1}][\csuse{postnote:##1}]{##1}}}
      {}}%
  \dolistloop{\cbx@sortkeys}}

% internal list of sorted entry keys
\def\cbx@sortkeysinit{%
  \ifcsundef{blx@sort@\the\c@refsection}
    {\ifcsundef{blx@slists@\the\c@refsection @entry@\blx@sorting}{}{\global\letcs{\cbx@sortkeys}{blx@slists@\the\c@refsection @entry@\blx@sorting}}}% Biber (mit Korrektur aus dem Kommentar von Audrey)
    {\global\letcs{\cbx@sortkeys}{blx@sort@\the\c@refsection}}}% BibTeX
\def\cbx@sortkeys{}

% Aus <http://tex.stackexchange.com/a/271373>
\DeclareMultiCiteCommand{\cbx@parencites}[\mkbibparens]{\parencite}{\multicitedelim}
\DeclareMultiCiteCommand{\parencites}[\cbx@cite@wrapper\cbx@parencites]{\cbx@cite}{}
\DeclareMultiCiteCommand{\cbx@textcites}{\textcite}{\multicitedelim}
\DeclareMultiCiteCommand{\textcites}[\cbx@cite@wrapper\cbx@textcites]{\cbx@cite}{}
\makeatother

\addbibresource{\jobname.bib}

\begin{document}

parencites: \parencites[vgl.][71-73]{Fruh.1992}[vgl.][427-429]{Weischenberg.1994}[vgl.][97]{Tuchman.1976}

\printbibliography 
\end{document}