WMV files not playing to completion in QT

[cohenst1]

I am having trouble viewing certain WMV files using Flip4mac (I use QT Pro to edit). QT only plays the first few seconds although it plays to completion in WMV9 and VLC. Am I missing a plug-in or is there another solution?

 

[NAG]

You sure it isn't just the file? Have you tried it on a different computer?

 

[cohenst1]

You sure it isn't just the file? Have you tried it on a different computer?

Thank you for your reply:

I only have two macbook pros. The older one has older versions of QT and F4M and the newer one has the latest versions. The problems persists on both. The odd thing is that if I download two files with the exact the same properties from the same site, one will work perfectly and the other will not.