Sounds work then they don't - AudioEmitter

In this part of my code in player.cs I get an error when trying to load this sound, but in another piece of code in another .cs (below) it works fine. I debugged it, and the filename var resolves to "starter.fps/data/staticobjects/fences/IronGateClose.ogg" which is exactly where the sound is that works in the other door.cs file listed below

... can anyone see what's going wrong?

error in Console.log...

Mapping string:  You picked up %1 to index: 15
AudioEmitter::update: failed to create source!
AudioEmitter::onAdd: client failed initial update!

here's the offending function...in player.cs

function Armor::onCollision(%this,%obj,%col)
{
   if (%obj.getState() $= "Dead")
      return;

   // Try and pickup all items
   if (%col.getClassName() $= "Item")
   {
      if (%obj.pickup(%col))
      {
         // play sounds for objects - ANDY H
         %key = %col.getDatablock();
         if (%key.pickUpName $= "a gold key")
         {
             %keySound = new AudioEmitter() 
             {
                 position = %key.position;
                 fileName = "~/data/staticobjects/fences/IronGateClose.ogg";
                 description = AudioClose3d;  //for loud sound
             };
             schedule(3000,0,deletethis, %keySound); //delete the sound in 3 sec.
         }
      }
   }
....

but in another file door.cs then same sound call works...

if (%door)
   {
      if (%door.isOpen)
      {
         messageClient(%client, 'MsgClosingDoor', '\c0Closing door');
         %closesound = new AudioEmitter() 
         {
            //datablock = %door.closeSound;
            position = %door.position;
            fileName = "~/data/staticobjects/fences/IronGateClose.ogg";
            description = AudioClose3d;  //for loud sound
         };
         schedule(3000,0,deletethis, %closesound); //delete the sound in 3 sec.

         %door.setThreadDir(0,false);
         %door.isOpen = false;
         MoveObject(%obj, %obj.closedPosition);
      }
   }