ASF duration is 29 secs, WMP plays 25 secs. How come?

I've created a custom ASF file containing compressed voice + screen streams.

The total duration of the file according to the header is 29 secs.

When opening it in WMP (using custom DMOs to play the streams), the file plays 25 seconds, and then the seek bar snaps to the beginning, but oddly, WMP continues to play 4 more seconds before stopping.

Looking at the ASF with ASF Viewer - there are 29 seconds of packets , and both "play duration" and "send duration" are 29开发者_JS百科 seconds. Why would WMP only see 25 seconds??

Thanks

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My guess is that the WMP progress bar is being updated before the packets are played, instead of after.

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I've seen this behavior when the ASF index was corrupted, i.e. when the index entry at 25 seconds points to the first data packet in your case.