I downloaded 3 WMV files All with the audio encoded by Windows Media Audio 9.1

Two of them play with no problem.

But, the third will only play the video with-out the audio unless I use ASFTools to re encode the audio to Windows Media Audio V8.

Why can I play 2 files that have the same audio Codec, yet can't play a 3ed one also with the same codec?

AVI Codec states that I have the necessary Coded to play WMA 9.1, and on 2 files that is correct.

Any ideas?