I recently ran into a fun little problem with the Helix Stadium XL and Streamlabs Desktop. And by fun, I mean the kind of problem where you spend a stupid amount of time wondering why the thing you can hear perfectly fine in your headphones sounds completely wrong in the recording.
The Stadium was connected to my Mac over USB-C. Streamlabs could see it. The audio meters were moving. I hit record, played a bit, listened back, and instead of hearing my processed Helix tone, I got the dry DI.
Beautiful. Nothing says modern guitar modelling like spending all that money on a floor unit and accidentally recording the sound of strings going straight into the void.
After poking around, Streamlabs wasn’t the problem. The Helix was just handing the Mac the wrong USB pair.
For the processed sound, Streamlabs needs USB 1/2. USB 7 and 8 are where the dry DI lives.
Line 6 explains this in the Helix Stadium USB audio documentation. USB 1/2 is the normal processed stereo signal. USB 7 and USB 8 are the special dry DI outputs for re-amping. Those DI outputs are great if you’re recording into a DAW and want a clean backup track to run through Helix Native later. They’re less great when you just want to record a video and hear the tone you spent ages dialling in.
On the Stadium XL itself, go into Global Settings > Ins/Outs and look for USB Out 1/2.
For my setup, I set USB Out 1/2 to Matrix Phones.
That’s the bit that fixed it. I’m monitoring through the headphone output on the Stadium, so I want the Mac to receive that same mix. If it sounds right in my headphones, I want Streamlabs to hear that. Setting USB 1/2 to Matrix Phones does exactly that.
If you’re using a different output as your main reference, pick that instead. Matrix XLR if your finished sound is coming from the XLR outputs. Matrix 1/4" if you’re using the quarter-inch outs. I wouldn’t use Direct Out for a basic Streamlabs setup unless you specifically know you want to route a preset output directly to USB 1/2. That option is useful, but it’s also the sort of thing that makes you think you’ve fixed the problem while creating three new ones behind your back.
The preset itself should also be doing the normal thing. Most presets output to Matrix (1/4", XLR, Phones), which is what you want here. The Line 6 output block documentation says that sends the path into the Stadium’s matrix mixer, where the 1/4-inch, XLR and phones outputs can all have their own mix. If you’ve built some complicated preset that sends paths straight to USB outputs, check that too.
On the Mac side, there isn’t much to install. The Stadium works with Core Audio, so it just appears as an audio device. That’s nice, but it also means Streamlabs treats it more like a microphone than a full DAW-style interface with nicely labelled stereo pairs.
In Streamlabs Desktop, I added it as an Audio Input Capture source and selected the Helix Stadium XL as the device. Streamlabs has this covered in their getting started guide, but the wording matters here. The Helix is an input device in this setup, the same way a USB microphone is. It isn’t desktop audio.
If you’re trying to record Spotify, YouTube, backing tracks, Discord, or some other Mac audio at the same time, that’s a separate Mac audio capture headache. Streamlabs has a Mac desktop audio guide that uses BlackHole for that. You don’t need BlackHole just to record the Helix by itself.
For reference, this is the setup that worked for me:
- Helix Stadium XL connected to the Mac over USB-C.
- Preset output going to
Matrix (1/4", XLR, Phones). Global Settings > Ins/Outs > USB Out 1/2set toMatrix Phones.- Streamlabs source set to
Audio Input Capture. - Helix Stadium XL selected as the input device.
- Monitoring from the Helix itself, not Streamlabs.
If you monitor through Streamlabs, you can end up hearing the guitar slightly delayed, which feels awful. Monitor from the Stadium if you can. It feels immediate because you’re hearing the unit directly, not waiting for the Mac to take the signal on a short tour of software land and then send it back to you.
Test it with an obvious preset. Pick something with a big delay, a silly amount of gain, or any effect that makes it impossible to confuse the processed tone with the DI. Record ten seconds in Streamlabs and listen back.
If you still hear the dry DI, you’re almost certainly grabbing the wrong USB output somewhere. USB 7 and 8 are the DI outputs. USB 1/2 is where you want the finished sound to land for this kind of setup.
Once I changed USB Out 1/2 to Matrix Phones, the recording finally sounded like what I was hearing through the Stadium. Which is all I wanted in the first place. Sometimes the hardest part of using modern guitar gear is convincing it to do the obvious thing.