First, make sure you have the latest ARIA Player update.

 

If you are still unable to change settings in the Ambience effects, there may be a permissions issue with the ARIA Plugins folder. To correct this, follow these steps:

  1. In Finder, navigate to Go menu > Go to Folder.
  2. Type or copy & paste the following location:
    /Library/Application Support/Plogue/Aria/
  3. Right click on the Plugins folder and choose Get Info.
  4. At the bottom under Sharing & Permissions, set both admin and system to Read & Write.