Site hangs on bouncing red balls!

I am getting feedback from visitors to my site that the site hangs on bouncing red balls - on desktop, tabs, mobile phones.

I am using only chosen few recommended wordpress plugins to compress JS and CSS. I have used the same plugins on other sites with other themes and have not encountered anything like this. Not sure if it is being caused by any plugin.

Could you please take a look to see why is this happening?

Hello there,

I am not sure if this is theme-related issue. Please try to disable all your active plugins and activate them one by one to find which might be the source of the problem.