iFiiDefender+ USB Audio Ground Loop Eliminator (Type A > A) 5V

Made a noticeable difference in the sound quality.I had been dealing with a heavy noise floor for a long time. Tried all the tips for solving ground loop issues and nothing worked. In my case it was what sounded like loud radio static on a dead station. I thought maybe I had a bad SM7B or interface and it was very frustrating. The mic and audio was always unusable due to a super heavy amount of white noise, more than you'd expect from a typical noise floor.This appears to have drastically lowered the noise. It isn't 100% but the audio is absolutely usable now compared to the hot trash I was dealing with prior.It's expensive for what feels like a fancy flash drive, but it was worth it in my case. The noise issue must've been something interfering from inside my PC, if you've done enough troubleshooting with ground loop noise and still have static and think it is your computer that might be the culprit, then this will likely help with your issue too. I also coupled this with a cable that had ferrite as well to further help with reduction.

The product didn't work on its own or with a power source. They do not provide a plug, and there's no label on the wire provided. Plus if you leave it plugged in longer than 3 minutes it will overheat and fry the USB stick and it fried my audio interface, Audient Evo 4, along it. Do not recommend this 50-dollar piece of plastic to remove ground noise.

I have an Focusrite Scarlett 4i4 external audio interface, which (important!) draws its power from its USB C connection to my computer's USB hub. I noticed that whenever I connected my piano keyboard's MIDI interface to my computer (also via USB), then the Focusrite added a 2400 Hz hissing sound to any signal routed into its Audio In. The reason was that this MIDI interface disturbed the ground signal in the USB system, which the audio interface needs to properly interpret the Audio In signal. Changing the MIDI interface (MIDI to USB) didn't change the problem, as the ground was disturbed already in the piano.This iFi Defender, removed the hissing sound completely. Two important things to consider: (1) I plugged the Defender between USB hub and the piano's MIDI interface (!), not between USB hub and Focusrite audio interface. (2) Make sure (!!!) you add a 5V (!!!) USB-C signal into the Defender's side; without it, the hissing doesn't go away; higher voltages short-circuited my system, causing me a major scare.So take a regular small (!) cheap iPhone charging block for this 5V side signal. I first used just some free USB power slot from my high-end Anker charger, which usually provides only as much power as needed, but more than 5V in this case apparently; here this literally overpowered the Defender and caused a crash; so don't make the same mistake.All that said, I am quite happy to finally having gotten rid of the hissing sound. The Defender seems expensive, but I am really happy I found a way to solve my problem finally! :-)

To get right to the point, I must have invested over $700 over the past few years, purchasing various devices that were designed and touted to filter out AC or USB noise. And some of them did a fairly good job - but not necessarily removing all the noise. In most cases these devices attenuated the noise somewhat, but the noises were still audible to a certain degree. So obviously, I ran out of patience with regard to any "new developments" in those areas.Now enter the iFi Defender. The more I read about this device, along with the fact that it's really not as expensive as competing devices, I crossed my fingers and purchased one. I've been experiencing lots of USB noise thanks to a noisy desktop PC. This noise manufested itself as constant buzzing sound. I have a USB hub attached to which I have 5 different DAC's plugged in. No matter which DAC I listened to (plugged into various desktop amplifiers), I would hear a very distinct constant buzzing noise. Depending on the time of day, this buzzing noise would be louder or lower - but still very noticeable.So I plugged in the iFi Defender to the rear of my PC, attached the power plug and plugged that into a line conditioner. I then plugged the USB hub into the iFi Defender. The results were immediate - a definite improvement with the buzzing noises now absent - but to be fair, it didn't filter out all the noise. If you put your ear up to the speakers, you could hear a bit of static noise. So nothing is perfect, however, of all the devices I've tried in the past, this one seemingly does the best. The only issue I have now is that when attaching the power cord (even when connected to an iFi linear power adapter), whenever I go to play a video or music (anything video oriented), I get a very high pitched RF tone that is steady. The moment I stop playing a video or music, the high RF tone stops.As an aside, I also purchased the iFi Silencer at the same time, which only slightly attenuated the buzzing noise. But when I plugged in the iFi Defender, everything changed - completely for the better.Folks, my AC power in the particular room where I have all of my electronics set up is noisy, and I have to use various Furman line conditioners to try to filter out some of that noise. But my desktop PC, which is noisy to begin with, has a tendency to pick up other power noise, and it gets transferred to my USB outputs. So this iFI Defender seems to do a very good job of attenuating most of the noise, but the ideal "cure-all" device that removes all noise has yet to be invented yet, I'm afraid.For the price and the fact that it does a good job attenuating (but not eliminated all) the noise, I'm giving it 4 stars.