Relatable to this post!
I've got a similar or same headliner noise on my 2017 86.. more interior rattles for my "new" car (Still have the rear deck popping sound from another post
http://www.ft86club.com/forums/showt...ht=wheel+noise).
My noise is also located right above the driver's head toward the back and goes away when I apply some upward pressure onto the headliner. The noise sounds almost like a loose screw on a hard surface, and only shows up when my car is on bumpier roads/highways where I'm going 70+mph probably due to some vibration. Didn't even know I had the new noise until the day I turned my music off.
Going to check out a Toyota dealer first and see if I can get a diagnosis cause this should fall under my warranty. If they can't solve it, I'm taking out my tools and following some guides!