Perhaps the plugin passC2value could help you but I wonder a little about what you want.
Why you don't use the C2 audio object. If you write your own code to play only an oggfile, IE users wont hear anything.
[Edit] Ok, with the call Javascript plugin this is easily possible - but i've ignored IE9 in the javascript.
demo
external javscript-file
Demo-capx (requires callJs-Plugin) <img src="smileys/smiley2.gif" border="0" align="middle">
the whole project (zip)
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[Edit2]If you really want to write a script within the file index.html then you can play with the other plugin - passC2Value. The coding should be similar. Just mention that when you export from Construct then the index.html gets overwritten. <img src="smileys/smiley2.gif" border="0" align="middle">
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