In Lectora Preferences, the General option has listings for the path to the Images, Audio and Video editors. I’d start by checking those paths to make sure they point to the correct program path. The path for my audio editor at the moment is C:\Program Files (x86)\Trivantis\Lectora Inspire 16\AudioEditor.exe on Windows 7. If you wanted to use a separate editor, i.e. Adobe Audition, you could point to that the same way.