Comments sometimes disappear after posting successfully?

We're having an issue with (so far) one particular user posting comments to various files. The user will randomly have issues with it not saving their comments, and other people are sometimes not getting the comments because of this. The user will enter the comment, and because they know there have been issues in the past, wait and watch it say that it did post, but when they or someone else looks at it, it didn't save. Has anyone else experienced this and is there anything on the box.com end that could be causing this, or could it be a browser issue? User is using latest version of Chrome to access box.com and add comments. This not happening on all comments, all the time; it's seemingly random.