I’ll be honest, this one took me five solid hours of pure hit-and-trial before I finally cracked it.
If you’ve ever tried to map your APC Mini’s faders to vMix audio controls through Companion, you probably know the frustration: the values don’t match, triggers won’t fire, and you’re left wondering if it’s even possible.

Well… it is. And now that I’ve figured it out, I’m going to save you those 5 painful hours.

Why This Matters

This setup turns your APC Mini into a real-time vMix audio mixer.
You’ll be able to:

• Fade volumes smoothly (no more instant jumps from 0 to 100).
• Control specific inputs with specific faders.
• Keep your hands off the mouse during a live show.

Step 1 : Hook Up Your APC Mini to Companion

1. Connect your APC Mini via USB.
2. In Bitfocus Companion, go to Connections.
3. Add the Generic MIDI module.
4. Select your APC Mini as both the input and output device.

That’s the boring part. now the magic starts.

Step 2 : Build the Trigger

From the menu, Click on Triggers and add a new trigger.

We need to make sure Companion only reacts when the right fader is moved.

Condition 1: MIDI Message Type

• Variable: Last Message Type Received (generic-midi:lastMsgType)
• Operation: =
• Value: cc
  This tells Companion: “Only listen for fader/knob movement messages.”

Condition 2: Fader Number

• Variable: Last Controller Received (generic-midi:lastController)
• Operation: =
• Value: 48
  This number is the fader ID. Each fader on your APC Mini has a different one.
  Tip: Move the fader while watching Companion’s MIDI debug panel to find its number.

Step 3 : The Action: Fade Volume in vMix

how to send the exact fader position to vMix.

• Action: vmix: Audio - Fade Input Volume
• Input: 77 (replace with your actual vMix input number)
• Fade to volume: $(generic-midi:lastValue)
• Fade time (ms): 2000 (for a smooth 2-second fade)

Important: vMix only supports volume values between 0 and 100, so make sure your MIDI values are scaled to that range. The APC Mini sends 0–127 by default, but Companion handles it fine here.

Step 4 : Test and Celebrate

1. Move your chosen fader.
2. Watch your vMix input’s volume fade exactly to your fader’s position.
3. Enjoy the fact that it works.

Extra Tips

• For multiple faders, duplicate the trigger and change the lastController value.
• Shorten the fade time for quick volume changes; lengthen it for smoother fades.
• You can also add LED feedback to your APC Mini so you see volume levels visually.

This might look simple now, but I fought with it for hours before finding the right combination of conditions and variables. Now that you’ve got the recipe, you can skip the frustration and go straight to mixing like a pro.