Acrobat Pro DC comment tools issues

We have a K12 enterprise deployment of Adobe Acrobat Pro DC version 2015.017.20050 on MacBook Airs running OS X 10.11.  Many of our students are having issues with edits from the comment tools sometimes not saving. Sometimes the highlighter will not work. Once they exit the program and go back in, it will then work. Sometimes their edits will disappear, they will exit the program, and the work will re-appear.
Additionally, some students are using the comment button and the thought button is not showing up on their document, but it is showing their comment in the margin. The issue isn't consistent but affects nearly 1000 devices on an irregular basis.

Is anyone else having this issue or have ideas for solutions?