The plugin currently has a minor performance bug, unfortunately that’s the bug you’re running in to.
The JavaScript attempts to prefetch all images in your banner before displaying anything. This is meant to make it so larger images don’t load in chunks (have you ever seen JPGs and PNGs load one line at a time? That’s what we’re preventing here).
I’m not sure how many images are in your banner, but each one is 1024x240px, which is rather large to begin with (>100KB). The delay is because the images are being loaded into the cache.
I’ll see what I can do to make it load the first image immediately (rather than waiting for all of them), but I don’t have an ETA for that fix. In the short run, you can try optimizing your images to decrease the image size. https://smush.it is a fairly good resource for optimizing what you already have. It should decrease most of your image filesizes by at least 10%.
