Random page size despite identical resolution on input images.

I have a minor issue.

Trying to combine 50 images in Adobe Pro works fine. But after the 51st image is added, page size starts varying up and down by >95%, even though every single image added has the exact same resolution and are non-compressed PNGs.

There seems to be no way to change the page size after Adobe has decided to randomize page size. All methods I've tried only change the size of the image on the page, stretching it out outside the page borders.

Has anyone figured out how to defeat the patented Adobe page size randomization algorithm?