It seems to me that it is a mistake to describe this as "open source" given that the license[1] has a commercial use restriction. The de-facto definition of what constitutes "open source" - The OSD[2] - explicitly disallows "field of use" restrictions (see clause #6).
It would probably be more correct to call this "shared source" or something.
It would probably be more correct to call this "shared source" or something.
[1]: http://www.audeering.com/research-and-open-source/files/open...
[2]: http://opensource.org/osd