Failed to load resource

If i load the sites with images twice the images disappears.

http://ericrohner.ch/index.php/spielplan

is there a problem with cache or cache cleaner ?

[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (pressefoto2.jpg, line 0)
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (pressefoto3.jpg, line 0)
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (pressefoto4.jpg, line 0)
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (pressefoto1.jpg, line 0)
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (Friseuse_s.jpg, line 0)

thx for help

found this solution that work.
the solution was to move the System - SEF plugin above the GK ExtCache plugin in the plugin order...
https://www.gavick.com/forums/124/images-disappear-after-page-reload-in-joomla-2-5-3-15160.html