Glitch in Slider

Hi Guys,
The slider plug-in you’ve made is great! Just having one problem with it. When on bigger screens the images in the slider comes up but it’s blurry. Normally it would just be like that while it’s loading but sometimes it just stays blurry until I stretch out or shrink the size of my browser. (It’s not because the file is too big because on my 13″ mac it loads fine.) Can you offer any fixes for this?

Thanks!

https://wordpress.org/plugins/hero-themes-gallery-manager/