Yes, it’s indeed rounding the sprite position. As pointed out by debugChicken on Discord, this specifically happens here because the anchor point of a sprite is set to the center, and its image is not an even-size. Cropping the image so its dimensions are even (eg adding a row of transparent pixels) or using Sprite:setCenter(0,0) resolves the issue.
I could imagine having a different method of rounding could give more predictable results (I’m not sure how it’s implemented currently), or alternatively have a way to set the sprite center with specific coordinates rather than a fraction (so you could round it down manually).
Anyway, ensuring that all sprites are of even size is a good enough solution for me. I’ll leave it up to you whether/how to make changes to the SDK 