Piwik 2.4.1 slow performance. Icons are loaded very slowly (no replies)

Hi there,

since we’ve updated to Piwik 2.4.1 icons/images are loaded very slowly. When I switch between sites it takes around 2-6 seconds until all images are loaded completely.

Are you able to reproduce this issue? ANy help?
This issue occurs on 2 Piwik installation