Runes won't save?

Runes won't save when I press the "save" button in team select. Even when the client asks whether I want to save the runes and I press yes, they still don't get saved. There is no error message either. I think this has been happening since the last patch. It's completely random, there doesn't seem to be a pattern to this. Happens about once every 7 games. Haven't seen anyone else complaining about this. What could be causing this?