Noraml way- Click on bounce on the output track or select :Bounce from file menu.
Set the begin and end points, select MP3, "add to iTunes",etc.
There are no regions selected but a track is highlighted which is the track that only gets bounce. Again, if I open a new song and drag regions into the new song it bounces fine.
Can the file get corrupted over the course of recording, editing etc.??
Brian