Some churches have already solved this problem. But I continue to be surprised by how many haven’t, especially those with high-end, expensive systems. I’ve walked into beautifully equipped rooms with pro-level gear, only to hear that familiar hum coming from their CG computers into the PA and stream mix. Meanwhile, I’ve seen smaller churches with modest AVL systems manage to avoid the same issue entirely. It doesn’t always track with budget or size, which tells me this is still a blind spot in many churches.
Leading a commissioning team early in my career for a new church AVL system, I noticed a persistent hum coming from the CG (computer graphics) channels, the ones handling pre/post-service music and all the ProPresenter video content. I knew the system was new and designed well. But something was off.
I called our system designer back at the office and walked him through the issue.
Me: “There’s a hum in the CG audio.”
Designer: “Headphone jack out of the Mac Mini?”
Me: “Yep. Into the $3 splitter cable you spec’d, then into two 1/4” inputs on the console.”
Designer: “Are you getting signal?”
Me: “Yeah. But it’s noisy.”
Designer: “Well, it should be fine.”
It should have been. But it wasn’t.
To be fair, these were sharp engineers. Maybe a little overworked, but this wasn’t a team made up of lazy or bad designers. It was just a classic case of real-world experience not matching what looked right on paper. And that moment taught me something I’ve never forgotten: when a TD, a volunteer, or someone without a tech degree says something sounds off, it’s worth listening. Not every anomaly is user error or the old ID-10T error. (Google it for a snicker.)
I didn’t win the debate that day, but I did fix the problem.
I dug around, found a stereo DI, dropped it between the splitter and the console, flipped the ground-lift switch, and just like that, the hum vanished. The system was clean. We moved on.
That’s Level One of fixing this common problem. But trust me, it’s still happening in 2025.
Why Your CG Audio Still Buzzes
You’ve got a computer (or a few) sending audio into your console or submixer: ProPresenter playback, pre/post-service house music, bumper videos, or feature videos. That audio is often routed through the computer’s 1/8″ headphone output jack, split with a cheap cable to two 1/4” or XLR adaptor plugs, and patched into the console or submixer, either right there or from another booth, stretching a long distance through balanced XLR lines.
It works. Technically.
But it buzzes, or it hums, or it sounds thin—or all three. And no matter how great your PA is, the CG content sounds like someone plugged in a clock radio.
It may feel like it some days, but odds are, your tech booth was not built over an ancient Indian burial ground. It’s just picking up the typical junk that unbalanced, poorly isolated connections tend to attract: electrical noise, RF interference, and ground loops.
Remember: no matter how powerful and well-built your CG computer is, the internal DAC (Digital to Analog Converter) and headphone amplifier circuitry are among the cheapest components in the entire machine. They’re designed to drive a pair of earbuds or desktop speakers, not high-quality audio for a worship space or streaming.
Do you really want to trust the sonic quality of your entire video playback to the lowest-tech part of the signal chain?
Three Ways to Fix This (Ranked from “Good” to “Best”)
Level 1: Use a Proper DI
If your only option is the headphone jack, get a good stereo DI box. The 1/8″ stereo plug from the computer’s headphone output typically splits into two 1/4″ plugs, one for the left channel and one for the right. Instead of plugging those into adapters or directly into the mixer, run them into the DI, then send balanced XLR outputs from there to the console.
Engage (or disengage) the ground lift switch, and in most cases, the hum will disappear. This is the most affordable fix, and it works more often than not. It was my first real-world solution, and it still holds up.
Level 2: Use a USB DI
Better yet, skip the headphone jack altogether and go digital.
A USB DI (like the Radial USB-Pro or Whirlwind PCDI-USB) connects directly to the computer via USB. It keeps the audio in the digital domain until it’s converted using a higher-quality DAC inside the DI, and it delivers a balanced, isolated signal to the console.
This completely bypasses the noisy, low-grade headphone circuitry in the computer, and the improvement is immediate. Connect two XLR cables from the USB DI to the mixer inputs, and you’re set with clean, full-range, hum-free audio.
Bonus: This is also the method preferred by audiophiles. In the high-end audio world, serious listeners routinely use external DACs to bypass the built-in converters in laptops, phones, and even dedicated audio streamers. Why? Because the internal DAC in most consumer devices is an afterthought: low-cost and noisy. No self-respecting audiophile spends thousands on amplifiers and speakers just to run the signal through a $2 chip and a headphone amp designed for earbuds. Same idea here. A USB DI is simply a higher-quality DAC than the one inside your CG computer, equipped with pro-audio features like XLR connectivity and ground lifts.
Level 3: Full Digital Audio Networking
This is the advanced option, and if you’re already running a Dante network, you likely have this covered. But for those who aren’t there yet, it’s worth knowing what’s possible. With Dante Virtual Soundcard installed, your CG computer can send audio directly into the network and into the console without any analog cables or converters. The signal stays digital from start to finish, eliminating noise and avoiding ground loops. It’s clean and fully integrated—but only if your system is already built to support it.
But even if you’re not there yet, Level 1 will still make an improvement. Level 2 even more so.
If your video content hums, buzzes, or always sounds like a bad mp3 file, don’t settle. You can try masking it with a noise gate or EQing it into submission, but that’s just treating the symptom, not the problem.
Start at the source. Fix the connection. Use the right gear. Ten minutes. Less than a few hundred bucks. A better experience for everyone in the auditorium and online.
And to my advanced friends: I know you’ve already got this sorted out. Cheers! Love it! #GOAT! Now go pay it forward; help someone still using a headphone jack and a $3 splitter. And while you’re at it, don’t forget to listen.
