NSImages blurred-out in Sonoma

My app uses various PNG images for parts of its UI. In Sonoma these images are rendered all blurred. It looks like I'm putting a 10 or 20px gaussian blur on it, which of course I am not. In prior macOS versions they have rendered just fine.

Occasionally some user action in the app will cause a part of one or two images to render sharply, but then it quickly reverts to the blur.

I have added the PNGs to the app as image set assets, providing 1x and 2x versions for light and dark modes respectively (so four images each).

I'm loading them using NSImage(named: ), and in most cases putting them into an NSImageView. I also use one of them as a patternImage:

if let image = NSImage(named: "RackFrame") {
    let color = NSColor.init(patternImage: image)
    color.setFill()
    dirtyRect.fill()
}

Both methods result in the same issue.

Any thoughts on what's going on would be gratefully received!