We are looking at this issue. But because of its intermittent nature, we are unable to reproduce the issue.
Can you share the sample files with which you are facing the issue?
Are there any specific softwares installed on your system?
You can mail me the files and information at firstname.lastname@example.org
AmanThomas King supported this idea ·Thomas King commented
It seems that the issue is happening with letter combinations that InDesign equates to a alternate glyph in the font. For instance "io" in Devotions changed to an uppercase O with a tilde. Sometimes it replaces a letter combination with a ligature. If you look on the attached file you will see whats going on.