Blurry Single Product Image WooCommerce

Hello there!

Recently I have created a new website about jazz transcriptions: https://www.jazzscripts.nl and https://www.jazzscripts.com.
Everything looks nice and works really well with the Enfold theme.
However, whenever I visit the single product pages of my shop or transcriptions page, all the images look blurry.

These are the display settings I use for WooCommerce:

Catalog images: 450 x 450 px (Hard crop on)
Single product image: 284 X 274 px (Hard crop off)
Product thumbnails: 120 x 120 px (Hard crop on)

I already have regenerated all the images with the Regerate Thumbnails plugin, but the problem still exists.

I really appreciate any help you can provide.

Philippe