[FIXED] Active Sims interrupt current interaction to do something else

I'm experiencing the same issue.

I've recently installed the newest patch(es) and Eco Lifestyle.  Everything was fine, though, until today, when I enrolled a group of students into Foxbury and sent them to live on campus in university housing.  Prior to this, I'd rotated between two families (in Newcrest and San Myshuno) and played each for a four-week sim year without any game play trouble.  I have not tried to rotate back to a typical, non-university household to test if they, too, will now experience this issue.

With the Foxbury household, actions are sometimes (not always) cancelled in favor of other actions.  Biggest issues are with writing term papers, refining and organizing the presentation board, eating meals, toilet/showering, painting, and playing computer games.  Sims very often abandon these actions and instead choose one of the following: mixing drinks, tapping the juice keg, doing push-ups, stretching, and playing with clay.

There are currently no active NAPs at Foxbury.  

I have no CC and only use one mod (MCCC).

EDIT: after reading around in this thread and in another, I'm thinking it's the NAP system, too.  I took a group to a public bar in Oasis Springs, and in addition to their actions continuing to be cancelled and replaced, townie sims were swiping up the tables, decorations, etc.  I've since unchecked the option for NPCs to vote, but the NAP behavior is rampant.