Troubleshooting Canvas View for Missing Highlights in Interviews

I'm having an issue with seeing all of my highlights in the canvas view. After interviewing one participant, I used the cluster feature to see how it would theme what was already present. But after performing several other interviews and tagging them, I don't see the highlights from the new interviews in the canvas view. However, if I convert the view to grid, etc, I can see the other new highlights. What's happening hear and how can I see all of my highlights in the canvas view?