The Xbox 360 supports videos in Windows Media Video (WMV) format (including high-definition and PlaysForSure videos), as well as H.264 and MPEG-4 media. The December 2007 dashboard update added support for the playback of MPEG-4 ASP format videos. The console can also display pictures and perform slideshows of photo collections with various transition effects, and supports audio playback, with music player controls accessible through the Xbox 360 Guide button. Users may play back their own music while playing games or using the dashboard, and can play music with an interactive visual synthesizer.
Try to answer this question if possible (otherwise reply "unanswerable"): When was the visual synthesizer added?
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