Captivate 7 and Audio Issues

Hi, I have been having with audio files in Captivate 7 when changing audio files for a specific slide. If I use the F6 functionality, sometimes the new audio file will be attached, sometimes it won't, and sometimes I will hear both audio files.

If I go into the library and remove all the audio files without first removing from the individual slides, sometimes the audio file will play on the slide when published. I cannot remove the audio file because I can see it in the library or on the film strip.

If I first remove the audio files from the slide, then remove the audio file from the library the file is definitely removed from the project.

Is this a bug in Captivate 7? Is there another way to ensure that the audio files have been updated without jumping through hoops. I've had a few projects I've had to recreate because of the audio issues.

thanks,