Add media (PDFs) broken in Boldial

Hi IsYoBoy
On a clear install (WordPress 4.4.2 and Boldial) I can’t get the [Add media] button to work in order to import a link to a PDF in my media library. Funny thing is: images do work. And even more strange: switching to another theme does work as well. There I can import the desired link to a non-image such as a PDF.

Now in boldial, I can upload or select a PDF but adding results in a titlestring without the actual link.
What am I doing wrong?

regards,
Cees Omes