Drupal 7.50: zip files only visible for admins


we have a view that shows downloads to certain roles. It works quite well, except with zip files. When I’m logged in as administrator, the zip files are displayed. When logged in as normal user, they are not. All other downloads are visible, however.

The file type is written as accepted file types in the file upload filed of the corresponding content type.
All users are allowed to view any files.
The mime type written into the corresponding file type.
Access control is in place and set to allow viewing of any content.
We use the media plugin, but I can’t find any setting that would limit viewing of zip files to administrators.

It still looks like a permission problem. I could, however, not find any settings that would allow me to set which role is allowed to view which file type.

Does anyone have an idea?

Drupal version: 

Source: https://www.drupal.org/taxonomy/term/22/feed