>>For instance when you replied to me, a short Goodbye was sounded through my speakers. I am pretty sure that this is a Windows settting, but I have no idea which setting it is, since I have all Windows program event sounds set to None.
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>That is an embeded sound sent at the page level. But, it is far from being a Goodbye sound. Could it be that there is a problem with the temporary files in the browser?

Is it an embedded WAV file? May I ask you to email the file to me, so that I can do some checks? I hear exactly the same sound on two different computers at two different locations.