Had a slight hum introduced into my system when I replaced solid state phono pre with all-tube unit. Not a huge believer in expensive power conditioners/regenerators, so I tried a few different power outlet combinations, with some success. But most significant improvement came from the iFi ground defender. My all-tube system, with efficient horn speakers, is now very quiet. Highly recommended.
This device successfully eliminated ground loop noise emanating from my PC! I was experiencing electrical noise coming through my studio monitors and this device attenuated all of the unwanted sound. I am currently using a desktop PC featuring an ASUS motherboard, and an external audio interface (UAD Apollo Twin X) with Yamaha HS8 speakers. For more information on whether this device meets your needs, please refer to this YouTube video: https://www.youtube.com/watch?v=3e0qE47pqqw
Perhaps it may work for others. But it did not work for me. Additionally, it messed with my PC power scheme, such that my PC would not shut off, when attempting to do so.