What players do the Windows Media Audio and Video 9 Series codecs support?
Content encoded with the Windows Media Audio and Video 9 Series codecs (except for the Windows Media Audio 9 codec) is not supported in Windows Media Player version 6.4. Content encoded with the codecs can be played in Windows Media Player version 7.1 and Windows Media Player for Windows XP; however, the codecs must be downloaded before the content can be played. Content encoded with the Windows Media Audio 9 codec can be played in Windows Media Player version 6.4. However, content encoded using VBR encoding with the Windows Media Audio 9 codec may have glitches or silence during playback. Content encoded with the Windows Media Audio 9 codec can be played in Windows Media Player version 7.1 and Windows Media Player for Windows XP; it is not necessary to download the codecs.