jwplayer 7.8前置视频广告不起作用

Question

我尝试使用自定义在jwplayer 7.8版中嵌入视频广告。但是它不起作用。请帮助我解决问题

           
                    playerInstance.setup({
   playlist: [{ image: "", file: ""}],
   advertising: {

      client:  "googima",
      schedule: {
        pre:{
         offset: "pre",  
         tag: "https://pubads.g.doubleclick.net/gampad/live/ads?iu=/14008522/video-jwp&description_url=https%3A%2F%2Flookandcook.com&env=vp&impl=s&correlator=&tfcd=0&npa=0&gdfp_req=1&output=vast&sz=400x300|640x480|970x90&min_ad_duration=10000&max_ad_duration=15000&unviewed_position_start=1"
      }
      },
      vpaidmode: "insecure"
   }
});