How to change hyphenation but not quotation marks in bibliography with biblatex?

Question

I'm using biblatex with biber and an authoryear style for my bibliography. My main language is french, but I have different languages in my bibliography (so I load \usepackage[english, french]{babel}. I would like biblatex to print bibliography items hyphenated according to their hyphenation field (e.g. no space before double punctuation and question marks), but always with french-style quotation marks. When I use \usepackage[babel=hyphen]{biblatex}, biblatex uses the hyphenation language (e.g.: english) quotation marks, but doesn't seem to use other rules (such as no space before double punctuation and quotation marks). That's exactly the opposite of what I'm looking for. When I use \usepackage[babel=other]{biblatex}, biblatex does use the right hyphenation rules, but still uses the foreign language quotation marks, and also uses the foreign language version of some strings (e.g. 'in' or 'cit. on').

I've looked around quite a lot but couldn't find a solution to this problem. Any idea?

EDIT: here is a MWE:

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[english, french]{babel}
\usepackage[autostyle=true]{csquotes}
\usepackage[citestyle=authoryear-comp, bibstyle=authoryear, natbib=true, babel=hyphen]{biblatex}

\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@ARTICLE{agnew_iv._1987,
  author = {Agnew, John},
  title = {{IV.} Place anyone? A comment on the {McAllister} and Johnston papers},
  journal = {Political Geography Quarterly},
  year = {1987},
  volume = {6},
  pages = {39--40},
  number = {1},
  month = jan,
  doi = {10.1016/0260-9827(87)90030-9},
  hyphenation = {english},
  issn = {0260-9827},
  shorttitle = {{IV.} Place anyone?},
  url = {http://www.sciencedirect.com/science/article/pii/0260982787900309},
  urldate = {2012-08-02}
}
\end{filecontents}

\addbibresource{\jobname.bib}

\begin{document}

 Some text.

 Some text, with a citation \citep{agnew_iv._1987}.

 And now a bibliography.

 \printbibliography
\end{document}

The output here is:

I would like the same but with French "guillemets" (quotation marks).

Answer 1

The problem actually comes from the autostyle=true option passed to csquotes. If you remove it, it works just as expected.