sometimes when open home page the revolution slider can’t load . I have

Hi to all,
I have a issue with my wordpress site. I create a new home page to replace the old one.
Now (sometimes) the revolution slider don’t working very well.
The browser don’t load the revolution slider and seems wait to load it. With refresh button could be appear the slider (sometimes remain the same).
The rest of page and the other pages are loaded  without problem.
 
I appreciate for your answer.
Best regards