var captchaImage = document.getElementById('captcha');
  var captchSound  =document.getElementById('captchasound');
  var cimg="";
  var csound="";
  var counter=1;

  function goimg(){ captchaImage.src=cimg; }
  function gosnd(){ captchSound.src=csound; }
  function chimg(ref,loc)
  {
   cimg=loc+"/import/securimage_show.php?sid="+ref;
   captchaImage.src=loc+'/import/i/clearpixel.gif';
   setTimeout("goimg()",1000);//clear image cache and set time out before displaying next image
   return false;
  }
  function chsound(ref,loc)
  {
   csound=loc+"/import/securimage_play.php?sid="+ref;
   captchSound.src='';
   setTimeout("gosnd()",100);//clear sound cache and set time out before displaying next image
  }