It means you have sorted your video list by filename. This can be changed in the web admin on the Orbiter page. However, this means, if you have multiple drives, and you spread your videos over multiple drives, you will not be able to have all in one list, but must know, where on the disks (or the NASes), your videos are. It is not the recommended setup, but is often used by people, who are used to more simple media player that don't see the whole picture, but just the directory structure.