It's been a while since I used the Shake effect for a video. I recently tried to use it on one of my projects, and it doesn't work right. Every time the effect window is loaded, it shows a different still of the clip moving around, but it doesn't shake whilst the video is playing (both preview & output).
How long has this bug been present anyway? The last time I used the Shake effect was before I updated to 5.01.
By the way, this bug only happens on images, and if their duration is under one second.