Video playback may stutter in Windows Media Center when frame rate changes occur

Applies to: Windows Vista Home PremiumWindows Vista UltimateWindows 7 Enterprise

Symptoms


Consider the following scenario:

  • You are watching live or recorded TV in Windows Media Center.
  • The frame rate of the broadcast changes, sometimes frequently.
 In this scenario, you may notice that video playback stutters or "glitches". In some cases, it may make the video almost unwatchable.

Cause


This occurs due to Windows Media Center resetting the video pipeline when a frame rate change occurs. Each time a frame rate change occurs, it may take a few frames for the video to recover. However, when frequent frame rate changes occur, video appear to constantly stutter or "glitch" without smoothing out.

Resolution


There is no known resolution at this time.

More Information


This problem occurs when broadcasts frequently switch between interlaced and progressive content. Interlaced content is shown at 59.94 frames per second (fps) while progressive content is shown at 29.97 fps. This problem has also been seen when a broadcaster incorrectly flags their content. For instance, interlaced content is incorrectly flagged as progressive content.

It has been reported by some users that switching to a different video card and/or graphics driver may lessen (or possibly increase) the symptoms noted in this KB article.