On the internet, nobody knows you're a mensch.
Well, it sounds like maybe the images aren't being scaled down to proper width before they're being cropped.
Given that the generic icon is being cut off on the right, perhaps the code is grabbing the upper-left 600x800, instead of calculating the 3:4 ratio from the actual width.
Maybe it could be an either/or choice: resize to width, or to height. That's what I do manually when I make covers: get something clean at width, resize to 600 pixels wide, then crop to 800 high. But I can see the argument the other way: clean up the height, too, then resize to 800 pixels high, and if necessary fill in the width borders with transparency.
cap
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