When I purchased my Dell UltraSharp U3011 I noticed that it had a 3.5mm stereo output. The monitor could accept audio through the DisplayPort or HDMI inputs. This feature allowed me to easily connect from my computer systems to the monitor, and from the monitor to speakers or headphones. As convenient as that may sound it was far from perfect. The monitor's audio output would have a really annoying "humm" noise. Eventually I chose to purchase a Creative Sound Blaster X-Fi, and the device does fix the problem. However, I have chosen to simplify my life by selling many items, but not jeopardize audio quality. I noticed that PAC sold a "ground loop isolator" and I chose to investigate this device. Images and details below.
Front of the package.
Back of the package.
The loop isolator has a 3.5mm male and female heads. When using the loop isolator you can notice a drop in volume between 10% to 20%.
When using the Technics RP-DH1200, or other headphones, there is a noticeable reduction in "humm" noise, about 80%!
When using the Soundmatters foxLv2 Platinum it is important to lower the volume on the speaker. The speaker itself emits it's own noise, and therefore the filter cannot remove that.
Overall I'm very satisfied with the results of the filter, particularly when using headphones. While this device is marketed for vehicle use the filter can be used at home.