Multiple image captions with enabled cache

Hi.
I have a problem with image caption.
It is displayed multiple times. Sometimes double, sometimes triple and even more.
Problem apears only after enabling cache. Without caching it works fine.

At the begining, captions were not displayed at all. So I added

JHtml::_('behavior.caption');

in components\com_content\controller.php. As someone wrote here http://www.joomlart.com/forums/showthread.php?87096-Image-Caption-not-working-J3.1.1-Jand-a-Blank-1.2.4
After it captions appeared, but multiple times (when cache enabled).
Here is screenshot
And here is the website
with cache enabled : http://m51.stronazen.pl/13-wpisy/astronomia/11-poczatekwszystkiego
and with cache disabled: http://www.m51.pl/13-wpisy/astronomia/11-dlaczego-wielki-wybuch

sorry for poor english :P