Google cast receiver framework (CAF) queueing images

Question

I am having trouble getting CAF framework to work with queueing jpeg images. I use SDK v3 to send QueueItem array to the receiver. I expect the cast framework to show me the images one by one and not just one image only. In my test, the input 'loadRequestData' has 4 images. But the cast receiver (on TV) shows only one image (whichever is pointed to by queueData.startIndex). Here is the javascript code for initializing the queue:

  /**
    * Initializes the queue.
    * @param {!cast.framework.messages.LoadRequestData}  loadRequestData
    * @return {!cast.framework.messages.QueueData}
    * or non-null Promise containing nullable cast.framework.messages.QueueData
    * THE loadRequestData (input parameter to initialize) ALREADY CONTAINS 4 ITEMS (jpeg images)
    * BUT IT SHOWS **ONLY ONE IMAGE** DEFINED BY queueData.startIndex.
    * IT DOES NOT SHOW OTHER IMAGES AT ALL (PLAYBACK DURATION ETC DO NOT SEEM TO HAVE ANY EFFECT)        
    */
    initialize( loadRequestData) {
        const queueData = new cast.framework.messages.QueueData();
        const items = [];
        for (const requestItem of loadRequestData.queueData.items) {
           const item = new cast.framework.messages.QueueItem();
           item.media = new cast.framework.messages.MediaInformation();
           item.media.contentId = requestItem.media.contentId;
           item.media.contentUrl = requestItem.media.contentUrl;
           item.media.contentType  = requestItem.media.contentType ;
           item.media.metadata   = requestItem.media.metadata;
           item.autoplay = true;
           item.playbackDuration = 2;
           item.preloadTime = 10;
           item.startTime = 0;
           items.push(item);
        }
        queueData.startIndex = 2;
        queueData.items = items;
        queueData.repeatMode = cast.framework.messages.RepeatMode.REPEAT_ALL;

        return queueData;
    }