I had the problem with B2 2016.11.1.2235 on both my laptop and desktop.

I could not tell whether it was Avast or the MS updates that were also installed.

So I uninstalled the MS updates and noticed the problem was still there.

I then uninstall B2 2016 on both systems and replace it with Avast 10.4.2233 on my laptop and installed B3 11.1.2236
on my desktop to see what happens.

I will let them both run for now to see if either of them freezes up again.
I will post back with an update later.