Woocommerce conflicts with menu plugin

On a clients website, I’ve used the Menu Image plugin, making the menu items images.
Only on the Woocommerce pages (and only on his computer, not mine), the menu images are very large. Can you tell what the problem is?

OK:
http://i58.tinypic.com/289k6sz.png

Not OK:
http://i57.tinypic.com/14bjcsj.png

The link is http://www.nl12.nl (I can send you login details if necessary)

https://ww.wp.xz.cn/plugins/woocommerce/