I have logitech keyboard with key that I use to mute sound in Windows. When some calls me on my mobile phone I have pick it up quickly and mute my computer. I wanted to add this key as a shortcut in TS3 that would invoke mute speaker functionality but I can't select it. When I'm in Settings -> Options -> Hotkeys -> Add and click "No hotkey selected" and finally click on this mute button instead of becoming as selected hotkey it mutes my windows sound.

Is there a way to use it for muting myself on TeamSpeak3?

Best regards and thanks in advance