Video vout is destroyed while visualization vout is reused for next track
This can be observed since 2.2:
Enable audio visualization for all files in prefs. Then, if you start the first video, video will open within the main window and the visualization in an extra vout window.
Now every time you hit next, the video vout gets destroyed, the visualization vout is reused for the new video and a new vout is created for the visualization.
This results in a swap of video / visualization windows every time you start the next video, which is quite ugly from a users point of view.