Happy new year everybody...

i'm trying to change the default category item ordering. In k2 category parameters, it's set to default, but i can't find a way to control what the "default" setting is... I don't want to change it in one category only, but set another option as "default".

Any help would be appreciated.

Happy New Year :)
The default is ordering by id, which in 99% of the sites is also most recent.
If you want to use ordering, you need to set the ordering setting to "ordering". The default ordering for all categories cannot be changed.