Internet Explorer Image Resizing

Hi guys,

I'm using your theme alongside a plugin called SmartLogo which pulls together logos for me in a nice grid.
This works perfectly well in Chrome, Edge and Firefox, however Internet Explorer does not want to play ball.

Have a look at the URL provided in both Chrome and IE, you'll see what I mean.

Have you come across this before? If so, any idea of what can fix it, e.g any custom CSS so that IE knows it needs to crop the images?

Many thanks,
Daniel