Hey Jose,
OK, the way I tackle this.
I create a K2 category called front page, which will have just items that are displayed on the fronpage.
I would then modify the FrontPage Category parameters so that it is Newest First.
Then point your menu item to that category.
Check your K2 category parameters / change menu item to K2 category type only.
Hope that helps.
Simon
K2 Support
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