Unable to retrieve more than my last 30 shared stories

This is the second time I have run into this issue in the last couple of weeks. If I look at my shared story list under All Shared Stories, I can only scroll through the last 30. If I look at the shared stories of someone else that I follow, I can scroll through many more than 30. When I use the API to retrieve more than 30 stories, my JSON parser (json.net), returns an error while trying to parse them.

Do you think that the 31st story has some kind of invalid character in the site name, author name or story, or is there a problem with the API itself? I’ll try to debug further myself later today. The last time it happened, I believe it was after getting the last 24 stories, so I don’t think that 30 is a magic number here.