Masonry grid floating issue

Currently have a situation on this type of page https://www.wearetoro.com/wp/pizzorno-2/ (artist portfolio page) where whenever you look at the page for the first time, all the images are overlaying each other; this issue then goes away when the user returns to the same page.

Has anyone had this before or could perhaps help find out whats going on?

This is the theme we are using: https://themeforest.net/item/brick-mason-premium-photography-and-blog-theme/245497

I am currently adjusting the CSS and HTML structure, but could it be the masonry script that’s breaking the grid?

The issue seems to persist on Safari even when returning to the same page.

Thanks in advance.