Can't edit in the Adobe Audition 3.0 I downloaded at TechSpot

I can open a file into Audition and listen to it, but when I need to edit, to cut or delete a section, for example, I highlight the section to eliminate, hit the delete button, and nothing happens. I then go to the Edit drop-down menu, only to find that "Cut" and "Delete Selection" are greyed out. How can I fix THAT? I need help.
 
Back