Hi Boomer,
That's interesting. On windows 7 you can go to the control panel and click on the SOUND icon and check a box to display the SOUND icon.
I use windows 7 Professional at home also.
And the MUTE should work.
Barring that, do your DESKTOP computer SPEAKERS have an ON/OFF power knob, wheel, button????
If so, you could simply turn OFF the power to the speakers and you would have NO SOUND.
My desktop speakers here in my office as well as at home have a power On knob. OR have you tried turning the VOLUME KNOB all the way to OFF????
Just some different ways to get you to keep it quiet for the "boss". lol!!!!
Give that a try please and let me know.
Thanks Boomer!
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