When using task switcher on symbian and running video test applications, the behaviour changes depending on the format of the video being played. When playing h.263, launching the task switcher and then returning to the test application results in video continuing. When playing MP4, launching the task switcher results in video stopping. It is not resumed when selecting the video test application.
Video test applications which show the issue can be found here: http://bugreports.qt.nokia.com/secure/attachment/20383/multimediakit.zip