Happened to me a lot when first installed (2016.12) seemed to be BFD3 related at first, as that seemed to be the common denominator, then it stopped doing it, then freezing AAS synths before closing seemed to do it, then it was ok again .....lately it's started doing it again every time I use the synthmaster 2.8 demo that I have been trying out.
 
 
 
 

Dupe - Forum software also playing up for me lately too.
 
 
 
 

For me, exit crashes have been cause by specific plugins in a project.
 
A few times it's been VST3 versions and when I replace them with VST2 versions, the crashes have disappeared.
 
Ralf - thanks for the tip about analyzing crash logs! :D