Gray "Video" box when editing SL

Help! Something has changed in a recent update that is making my video appear as a gray box within the editing stage in Storyline. The video plays fine, but as soon as I pause the timeline to add audio or shapes to highlight parts of the video, the gray box is back. It is impossible to overlay shapes or line up audio when I can no longer see the video on the slide. How do I fix this?!?