We had some issues with our wmv videos in the Media Player plug-in. When I changed the filter.php class ID for Media Player to the new ID things cleaned up nicely.
The current moodle filter uses the Media Player 6 plug-in. To use the "latest" version 7 or higher plug-in edit filter.php and change the Class ID to: "clsid:6BF52A52-394A-11D3-B153-00C04F79FAA6"
According to MS, the 6 plug-in is on our systems mostly for testing purposes. Less overhead but also less features and quality.
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