Can't play audio file but code seems right and audio file is not missing

programming flash
1

Hello,
I have a large flash simulator that is supposed to play a sound called sound2.mp3. This file sits in the “audio” folder next to the .fla file. The code that should play the sound is:

package {
     public class UnassignedQueue extends Sprite {
          private var soundURLRequest:URLRequest;
          private var soundNew:Sound;
          public function UnassignedQueue():void {
              ...
              soundURLRequest = new URLRequest("audio/sound2.mp3");
              soundNew = new Sound();
              soundNew.load(soundURLRequest);
          }
          public function playSound():void {
               soundNew.play();
          }
     }
}

(Note that all necessary classes are imported.)

This results in “SecurityError: Error #2000: No active security context.” But the sound2.mp3 file does exist in the audio folder.

I have reproduced the code in a simple class using the same folder structure and it works there even though it doesn’t work in this larger project.

Any thoughts on what’s wrong?