Need Help: 3Dio FS XLR + iRig Stream Pro Duo I/O Causing Feedback When 48V Phantom Power is On (TikTok/YouTube Streaming)
Hey everyone,
I’m trying to set up my 3Dio FS XLR binaural mic with my iRig Stream Pro Duo I/O and Samsung S24 Ultra for streaming ASMR on TikTok & YouTube Live, as well as recording video/audio on my phone, but I’m running into a major issue:
The Problem:
Whenever I turn on 48V phantom power on the iRig, I get a constant hum/buzz/feedback noise, even when I'm not speaking.
If I turn off phantom power and power the 3Dio using its 9V battery, the hum disappears, but then I lose direct monitoring through the iRig.
According to 3Dio’s official website, they recommend turning off the 9V battery power on the mic and using 48V phantom power from an audio interface like the iRig. However, that’s when the feedback happens for me.
Additionally, I’ve noticed a huge difference in gain levels when switching between phantom power and the 9V battery:
With 48V phantom power ON: Even with the iRig’s gain set to 0, loud sounds clip when the mic is 12 inches away.
With the 3Dio’s 9V battery ON: I have to set the iRig’s gain to 6 or 7 just to get a proper volume level.
This makes me think the phantom power signal is too hot, but turning down the gain doesn’t fix the clipping, and I still get the hum.
My Setup:
Microphone: 3Dio FS XLR (XLR L/R Outputs)
Audio Interface: iRig Stream Pro Duo I/O
Phone: Samsung Galaxy S24 Ultra (connected for TikTok/YouTube Live streaming & video recording)
XLR Cables: Hosa HMIC-005 Rean XLR3F to XLR3M Pro Microphone Cables (5ft)
Power Adapter for iRig: D’Addario AC-DC 9V 800mA adapter (filtered output for noise-free operation)
Powering the 3Dio: Either via its 9V battery or using the iRig’s 48V phantom power
What I've Tried:
Using the 3Dio’s 9V battery and turning off 48V on the iRig. I’m not sure if this forces the iRig to run on my phone’s power or its internal battery, but it stops the hum.
Using a USB hub between the iRig and my phone. No change.
Using a different power source for the iRig (powered via my phone instead of a wall outlet). No change.
Using high-quality shielded XLR cables (Hosa HMIC-005). No effect on the hum.
Adjusting gain settings on the iRig. Even with gain at 0, I still get clipping when phantom power is on.
Moving the phone away from the iRig (RF interference check). No change.
Turning on Airplane Mode while keeping Wi-Fi on. No change.
Bass Roll-Off (High-Pass Filter ON vs. Flat). No effect on the hum.
Potential Solutions I'm Considering:
Trying a ground loop isolator (like the Behringer HD400) to see if it reduces the hum.
Using an external phantom power supply instead of the iRig’s 48V phantom power (like the Radial StageBug SB-48).
Testing alternative ways to power the iRig (e.g., running it on battery instead of the phone or wall power).
Questions I Need Help With:
Has anyone successfully set up a 3Dio FS XLR with an iRig Stream Pro Duo I/O for mobile streaming?
How can I eliminate phantom power noise while still using the iRig?
Is there a way to fix the phantom power gain/clipping issue so that I can use the 3Dio as recommended without distortion?
Why does direct monitoring stop working when I power the iRig via phone battery and use the 3Dio’s own 9V battery?
