RedShop Product Image Formatting

For some reason some products are shifted down to the next row even though all images are the same size. I have tried replacing all images with the same size images, changing the thumbs in the config to a narrower width, changing the right width of the template lower and the images still skew down to the bottom row. Image attached. URL is http://diamondjgallerysa.com/pre-owned-watches/category/1/299/men-s-watches/men-s-watches.html?start=6

redshop.png

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