I have experienced a strange problem in Greek character rendering. We have used "Math_PI" font for greek characters and it display correctly in the story mode and not in the page mode in some places (in page mode it shows alphabet character instead of Greek). This problem identified in the particular place and not for entire article.
Please find the below screen shot for your quick reference. The highlighted character "f" should be greek "gamma" which rendered correctly in story mode but not in page view.