Interesting. I can confirm that behavior of the announcements in New Posts. I mean, New Posts is displaying announcements in this way:
http://www.forosperu.net/announcement.php?f=XXX&a=YY
Where XXX is the forumid of the latest forum (sort order) when you go to
AdminCP >> Forums & Moderators >> Forum Manager
But the issue appears to be that announcements are being displayed in New Posts when they shouldn't be
according to vbenhancer. So a stock, unmodified vBulletin 3.8.x installation shows announcements in New Posts yes or not? That's what we need to know