How to use a keyboard/mouse shortcut to toggle volume of a specific application (not master volume)

I am looking for a way to control the volume of a specific application from a keyboard shortcut. Specifically I want to mute Skype when I press a button on my mouse (Logitech G502). Something that might make this easier is that I can assign a key to open a program (or a shortcut of the volume mixer I have on my desktop), make multiple keystrokes, etc. I feel like this should make it easier, but I haven't come across a way to actually toggle the volume of a specific application yet.

The most useful information I've some across so far is making a shortcut to the Volume Mixer on my desktop by making a shortcut to %windir%System32SndVol.exe -T 99490633 and opening the volume mixer via win + B, left/right, and enter.

All of these things can be done fairly quickly with a simple command assigned to the mouse, but I haven't found any info regarding controlling the volume mixer via the keyboard or any shortcut of the sort.

Any help in achieving this task would be greatly appreciated.

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