Hi,
I've got a serious problem with Vegas 4.0c under Windows XP.
With a clean install of XP and vegas 4, when I add a video file with mp3 audio compression to the timeline, it works fine. (peaks are built)

But, if I install a new mp3 codec to encode at higher bite rate than 56kbps (Xp defaults codec), for example Fraunhofer IIS MPEG Layer-3 Codec (professional), I got the message : "Audio stream could not be determined MPeg layer 3" when I select a video file from the Vegas explorer.

I verified that the codec is well registered, all is ok, I don't understand where is the issue.

I tried with Klite codec pack and it does the same thing.

I must uninstall the codec and reinstall the windows xp default codec (which is limited at 56kbps rate for encoding...) to retrieve vegas works again with Mp3 video/audio encoded file...

Any idea ?