You need to make sure that you install Visio 2013 Volume, not Visio Retail. As long as your Visio 2013 is Volume, activation should be done with Office 2013.
Hello everybody, downloaded and used KMSnano V14 on my Windows 8 (genuine) install, activation of office 2013 pro plus worked like a charm. But for some reason, KMSnano V14 does not activate visio 2013 pro or project 2013 pro... any help is very much appreciated