Hello,
I don’t see described issue with the home slider https://gyazo.com/327d73ef31c6358c7c25802d808d1692 But I would suggest you to optimize slider images using Tinypng https://tinypng.com/ , you can save up tp 80% http://prntscr.com/p9wttv Also, install cache plugin. Because at this moment home page size is huge http://prntscr.com/p9wvkl and page speed is not very good and it could be one of the reasons of your problem – your browser just needs time to load slider image.
Regards
