I've noticed on some of my feeds, that when there's a 'red' item (intelligence trained to hide) before anything else, that hitting the 'j' key to view the next item will bring up the red item first. This is mostly an annoyance, but definitely not expected behavior.
It's happened on several different feeds; I'm using Chrome on ArchLinux, but it's also happened on Chrome on OSX. I'll test Safari to see if it happens there. Username in newsblur matches my username here.