Multiple sims have issues with using objects

Have been finding lately that when 2 or more sims try to interact with an object the action ends and the sims just stand there.  Examples: 3 sims at table having a meal and talk.  Neither action completes.  2 sims attempt to wohoo in shower.  They change into towels, one enters, and the attempted action cancels leaving them there.  As it currently stands, an object can be used by only one sim at a time.