After installing the CU (May 2015), the RBS is not storing files anymore, instead they are kept in the database.

Prior CU installation, when i uploaded a ZIP-file, it was stored in the "Blob"-directory, shredded in 1MB files, as it should be.
But after the CU-installation, the file is stored in the database.

I can edit, download and delete the file, no errors.

I did not change any settings regarding RBS.

Do i have to reinstall/reinitialize RBS ?

Hi,

After installed the CU, do you restart the computer?

Check if there is the relative error message in the ULS log.
If you cannot find any information about the issue.You can Reinstall/Reinitialize RBS to check if it can work.

check the articles below.

https://technet.microsoft.com/en-us/library/ee748649.aspx 

http://blogs.technet.com/b/bogdang/archive/2014/12/04/install-and-configure-rbs-with-sharepoint-2013-and-sql-server-2012.aspx