Karlankas te transcribo un ejemplo donde usando realaudio, ejecutan un ".ra" en un onmouseover y lo detienen en un onmouseout.
No es exactamente lo que buscas, pero quizás analizarlo te ayude.
Código:
<HTML>
<HEAD>
<SCRIPT LANGUAGE=JavaScript>
function play(fileName)
{
document.real1.SetSource(fileName);
document.real1.DoPlay();
}
function window_onload()
{
var plugInInstalled = false;
if (navigator.appName.indexOf("Microsoft") == -1)
{
var plugInCounter;
for (plugInCounter = 0; plugInCounter < navigator.plugins.length; plugInCounter++)
{
if (navigator.plugins[plugInCounter].name.indexOf("RealPlayer") >= 0)
{
plugInInstalled = true
break;
}
}
}
else
{
if (real1.readyState == 4)
plugInInstalled = true;
}
if (plugInInstalled == false)
window.location.replace("NoRealAudioPage.htm");
}
</SCRIPT>
<OBJECT classid="clsid:CFCDAA03-8BE4-11CF-B84B-0020AFBBCCFA"
id="real1" VIEWASTEXT>
<PARAM NAME="HEIGHT" VALUE="0">
<PARAM NAME="WIDTH" VALUE="0">
<EMBED name="real1" id="real1"
BORDER="0"
CONTROLS="play"
HEIGHT=0 WIDTH=0 TYPE="audio/x-pn-realaudio-plugin">
</OBJECT>
</HEAD>
<BODY onload="window_onload()">
<A onmouseover="play('Evil_Laugh.ra')"
onmouseout=document.real1.DoStop();
href="#">
<IMG src="AdvertImage1.jpg" border=0>
</A>
<A onmouseover="play('Whoosh.ra')"
onmouseout=document.real1.DoStop();
href="#">
<IMG src="AdvertImage2.jpg" border=0>
</A>
<A onmouseover="play('Explosion.ra')"
onmouseout=document.real1.DoStop();
href="#">
<IMG src="AdvertImage3.jpg" border=0>
</A>
</BODY>
</HTML>
Suerte.