Smush Pro is conflicting with a slider plugin

I have a slider half way down this page which shows the company’s clients. When I have Smush Pro active it seems to cut off the images. I have enabled to Smush Pro so you can see the problem. Is there any way to fix this?

I have attached 2 screenshots so you can see how it should look, and how it looks with Smush Pro on.

The website is built with the Themify theme and the slider added through their themify builder.

As an extra note, it seems to resolve if you refresh the page but on a new visit, it goes back to displaying with the issue.

I hope that’s enough information, but let me know if you need to know more.