I had the same problem. This seemed to answer it for me https://bugs.launchpad.net/ubuntu/+source/virtualbox/+bug/1443152
Pretty much uninstalling the virtualbox.org version and installing the debian package fixed it.
I had the same problem. This seemed to answer it for me https:/ /bugs.launchpad .net/ubuntu/ +source/ virtualbox/ +bug/1443152
Pretty much uninstalling the virtualbox.org version and installing the debian package fixed it.