SDR model - Sed export output raster shaped in weird "stairs" pattern

Hi!
As the title says, my sediment export output raster displays a weird stairs pattern across the landscape (SDR.jpg). Like the sediments are not flowing smoothly on the slopes. Same thing with the other model outputs, but the effect is less pronounced. I don’t get this outcome with the NDR model outputs (NDR.jpg), they flow smoothly (which is what made me question), yet I use the same DEM in both models!

Any idea? Is it normal?

Thank you very much!