UR44 and Ground Loop

Hey all. I’m new here. First post. I bought the UR44 after much research and I am very happy with the device, for the most part. I love the i/o options. The mic pre’s are great, very low noise. My problem is with the line-in for 1 and 2. I suspect I’m getting ground loop noise and I don’t know what to do about it. I’ve tried going into other rooms, and using a ground lift plug, turning lights on and what-not. It’s not making a difference and it’s bugging me. I really hope it’s a ground loop issue and not hardware.

Is there a sure-fire way to test that it isn’t hardware?

If it is a ground loop issue, do you have suggestions about how to fix it?


Hi bbisaillion,

Any time I’ve experienced ground loop issues, it’s been due to “dirty” hydro or incorrect wiring.

The basic idea behind a ground loop is, if you plug the UR44 into one circuit, and an input device (keyboard in my case) into another circuit, sometimes the grounding will come through one of the devices because that device provides the path of least resistance for the ground. I had this happen at home after I plugged my two Bose speakers into one circuit and my Tyros 5 keyboard into another. There was terrible hum. After I connected everything into the same source power, the hum was gone.

Now, I place all my devices on one clean circuit, that is, no lights, dimmer switches, or small motors. This is how I fixed my issue. Give it a whirl, and then post back :slight_smile:.

  • Lee

My UR44 has a noticeable hum when the USB cable is not connected to my computer.
The computer is often not connected to any power source, yet it resolves the hum issue.

I use both (Hi-Z) inputs at the same time to play my “Chapman Stick”.
I use (Phones 1) as my output to my home stereo amplifier.

The UR44 works great as long as I keep my USB cable connected to my home computer.

This issue was acknowledged (well one very similar one where there were no monitors plugged in) on smaller UR units (22?) Steinberg re-engineered them to fix the issue - I suspect UR44 owners don’t notice as much coz 44s tend to be used more in fixed studios rather than on the road.