After having added a button called "Playback Buttons" to VLC 2.1.3 (Rincewind)’s
control-panel which afterwards wasn’t removable, I went in through
C:\Users\Users_Name\AppData\Roaming\vlc (%appdata%\vlc)
and opened “vlc-qt-interface.ini” as .txt (Notes) and scrolled down to (MainWindow)
“MainToolbar” and erased “40-4;”. Same thing with 2.1.5. Problem solved,..for me.
Developers need to look into this bug.