I have an Alvin DM05 (newer type with the hidden clip attachment) and it rattles a bit, seemingly in the hardness indicator up top.
I can’t really see how it comes apart - I can unscrew the grip, revealing the clutch & spring. I can remove the top cap and the eraser. I don’t see how to get it any further apart.
Any advice? I like this MP pretty well: nice grip, heavy weight, clean design. If it didn’t rattle I’d like it better!