This player is set to load a Liverail and a DoubleClick ad at the start of the video, in 30th second and in 60th second. If the first ad returns empty, it tries the second ad. It works that way in both pre-roll and mid-roll – at the start of the video, in 30th second and in 60th second.
Learn how to serve VAST and VPAID ads with your videos in this guide - How to Use VAST/VPAID
