Problem with real-time Map over https



I have a problem with the real time Map, if I open the map, I get only a white screen.

Access to the site is via https.

If I try to open the real time map, it looks like the normal screen with the period in the left corner and under the period stands “Loading Data”.
After a few seconds, these two things disappear and the screen will be white.

If I try to access the site via http and the IP, everything is looks fine.

I use the Piwik version 2.10.0.

What can I do?