Super key to pause, mute mic, and mute speakers in windows

#z::
soundget, isMute, MICROPHONE, MUTE
if isMute = Off
    toMute = 1
else
    toMute=0
SoundSet, toMute, MICROPHONE, MUTE
return

Would toggle the mic's muted state on win&z. Muting master volume would be much the same, except instead of MICROPHONE you would put MASTER, however if it's just your media player you want muting it may be better to set up a hotkey to pause it, rather than mute system volume. Depending on the player it may be able to do it itself, otherwise look into the ControlSend function.

(This has the advantage of not using NirCMD, as while it's a brilliant tool, the ~.5 second disk lag is really annoying to me :()

I would recommend 'MicMute' utility to mute or unmute the primary microphone using a keyboard. It has a nice taskbar icon, taskbar balloons, and auditory notifications you can modify.

What's awesomer it also let me select my keyboards extended media keys as a shortcut - I choose the button next to my system volume mute.

you can do this and much more by using NirCMD along with AutoHotKey.

Take a look: http://www.nirsoft.net/utils/nircmd.html

NirCmd is a small command-line utility that allows you to do some useful tasks without displaying any user interface. By running NirCmd with simple command-line option, you can write and delete values and keys in the Registry, write values into INI file, dial to your internet account or connect to a VPN network, restart windows or shut down the computer, create shortcut to a file, change the created/modified date of a file, change your display settings, turn off your monitor, open the door of your CD-ROM drive, and more...