Probably the most common reason to hear the annoying IE clicking sound is that a page is set to refresh every so often, and each and every time that sound will be played. It could also be malware doing something nefarious.
You must like being under constant threat of malware though, since otherwise you would have switched to Firefox or Opera to get away from that. Can't say as I share in your devil may care attitude, but best of luck to you.
I know that I can go to sounds to disable the "Start Navigation" sound. But, I don't want to disable it until I know WHY it's clicking for no reason. I understand that when I open a new web page that the sound happens, but why is it happening when I'm away from the PC? If I have all programs closed and I'm just lying in bed, I hear the "click" sound of the "start navigation" sound.
I know HOW to get rid of it. It's an easy fix. But, WHY is it happening? I want to know if there's a bad program on my computer that is trying to access the internet while I'm not using it.
Thanks

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