Markers Disappearing in Team Project

Having a problem with Markers disappearing when working in a team project. My collaborator will make markers on the source media, update it, and I will see it briefly but then they disappear for all of us. Based on some earlier threads it seems like this was a bug issue at one point. What is the cause of this? Can I retrieve the markers?  XMP preferences are unchecked for all of us. I've also looked through the auto-saves and don't see them. No one is importing new media so I don't think that there are new clips overwriting the old ones.