ENDER V3KE priting 2x smaller

So, I have this Ender V3 KE, and it pretty much works correctly, except that all my prints are 2x smaller than they should be. I’m always having to double the scale of the prints in the software. I’ve tried with Creality and Orca Slicer, and both are giving me the same result.

Let’s say I have an object that is 40mm x 40mm x 10mm. If I don’t scale it by 200%, the print will be 20mm x 20mm x 5mm.

Is there any way to fix that?

You haven’t got something like CAD set to inches but the slicer to centimetres?

You have this problem will all files or only the ones you created yourself with CAD-software? If so, it must be a setting like Bonfireman is saying…