Edit: I stand corrected, there is a specialized CE certification that reviews limited fitness for purpose, although it does not seem very comparable to something like FDA requirements for double blind testing etc., so I'm still highly skeptical. Original comment:

There may be something here, but their presentation leaves a "snake oil" impression. Mostly because of their repeated emphasis on "CE" certification, as though that had any bearing on the effectiveness of this treatment. They even say it has "CE-mark certification for the treatment of tinnitus", which is really misleading, as CE simply means it complies with certain regulations regarding the construction of electronic devices, nothing at all about fitness for a given medical purpose.