VLC 2.1.1
OS X 10.9
Every time when a video with A S S subtitles is opened, VLC will freeze for a couple of minutes before the video starts playing. The only exception is when the last played video is the same video.
Videos with SRT subtitles or without any subtitles are fine.
This problem once occured in earlier versions (https://trac.videolan.org/vlc/ticket/4075) and it was fixed. Now it's recurring.