I think you are hitting a known bug in 11.7.700.169
Either install an earlier version from http://helpx.adobe.com/flash-player/kb/archived-flash-player-versions.html
or wait until the new version is released later this week.
Thanks for your explanations.
If the bug is known and a new version is released this week, i'll wait the correction.
Sorry, my mistake - I just realized that "Patch Tuesday" is next week.
problem solved with the last version
thx for your help