I did a factory reset: no changes. Culprits are Vision Provider, Multimedia and a bunch of camera related processes (CMH provider, mlp, faceprovider and so on).
By the way, before factory reset I disabled com.samsung.cmh: two things happened:
- Stories disappeared from Gallery (very good)
- Camera app continuosly crashed (not so good)
Now I will try disabling something else. I will let you know if things start improving.