Unstaged Files sort order constantly changes

After a file change, SourceTree seems to take several seconds to figure out the proper file sort order and as its doing this, it keeps updating the order of files shown in the Unstaged files section.

The problem is that if I'm trying to look at a diff on a file or discard changes to a file or really any operation within the first few seconds I go back to SourceTree after some code changes, the sort order changes on me while I'm selecting files for some operation.  I've discarded changes on the wrong file a few times as a result of this, losing some work.

This is most easily reproduced by simply pressing F5 multiple times and watching the files all dance around in different orders every time.

The normal use case is to have a set of several pending changes to various files, then make one more change to one of the files and go back into SourceTree.  Left click on a file to view the diff and the sort order changes.

See attached screenshots illustrating the issue.