mobile 404's on images, but images do show


I have used this tool a lot to get my site well-optimized and recently found the option to test as a mobile device. When I do this, I still get all A’s and a B, but at the bottom of the waterfall, there are 6 items highlighted in red that show 404. These are the 6 images (including the header and footer images) on the page. What is odd is that all of those images show up just fine on all mobile devices I have tested with, and even in the small preview Webpagetest shows (well, I can see the header).

It is a WordPress site, updated, using the Karma Wordpress theme. Various tests show my site well-optimized, but this 404 on mobile is confusing to me.

Any ideas? Thanks y’all,