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Generally when there is a problem with MP3 audio, one widely suggested fix is to convert them to WAV. Corel (formerly Ulead) programs seem to handle WAV audio format better than MP3. This is especially true when you are going to include them with video. MP3 can be nothing more than a video/audio file, having the video stripped away. So when you try to insert an MP3 into some video applications, the program may fall over trying to find the video, which is not there.
Ron Petersen, Web Board Administrator