doesnt work in Visual Editor (4.4.2)

Do you have active the checkboxes for this post type?
Have you active the second item bar of the visual editor – use the last button in the first line of the editor.

Can you add a screenshot if the editor and the settings?

You must open the second bar of the visual editor. Click the penultimate icon, the second from right and you open more functions, buttons of the visual editor. In this bar is also the AddQuicktag custom buttons.
Here you fond more about row 2. – https://en.support.wordpress.com/visual-editor/