There are a variety of devices advertised as a 'Windows USB Volume Control Knob' that can be reprogrammed very easily (without any additional software) so you can use it for other purposes.

Search for "Mini USB Volume Control Knob Audio Adjuster" and you will find a whole bunch of them. Many of them are made by a company called iwit, even if they don't say they are. i.e:
https://www.amazon.com/A...id=1591736563&sr=8-1

They offer an interesting way to change what it keys it can emulate. i.e.: most people don't know that Windows supports F13-F24 because we have not seen keyboards with those since, well, long before most of us had PCs. This unit will support those extra keys, and vMix does too.

You can set a 6 different shortcuts.

Press Dial
Press Dial Long
Dial counter clockwise
Dial clockwise
Press Dial while turning it counter clockwise
Press Dial while turning it clockwise

I use it for jog shuttle use, for example.

Here is how you reprogram it:
startup 'notepad' in Windows and make sure your cursor is sitting in the top left hand corner of notepad.

Hold the dial down on the iwit unit, and plug the controller into the PC.

Let go of the dial.

It will now print out a menu on the screen.

Use the dial to go up and down thru the menus. Find the option you want to change (changing the counter clockwise vol down to F13 for example), select it, go back up one menu, set the rest the same way, then click save.

It is now written to the device's memory. As a result, you can connect many of these devices side by side to do different things with different shortcuts. After that, use the find feature in the vMix shortcuts to assign it to whatever you want.

Hope you find it useful.
Jeff




More info can be found here:
http://www.expresii.com/...urface-dial-alternatives