[mib91]

  Don`t know exactly (I`m not electrician) but Your powered USB-hub (from PC) might have additional capacitors(filtering) that stabilizes power feed and filters noise coming from PSU/Motherboard/Hard-drives etc. There`s lot of info on internet about bad USB cables and noise issues when using USB power-feed.
 
For example, I cut-out power pin of my Aune T1 USB cable (since it gets its power from external brick) and no issues since then.
Before I got occasionally (very rarely) "noise/cracks/clicks" out of my PC. Also, they say that USB-powered DAC`s or Amps can have reduced SQ due to bad quality cables due to interference to data +/- lines. Though, there are different opinions to this since data is being transported in binary not as analogue.

Hey man, that notorious noise issue I was having months ago seems to come back again to hunt me. Since I changed the cable the noise almost became nonexistent. I checked on multiple computer and the noise often generates even when there is no media(song/video) playing.
 
I looked on internet and found this video having the same kinda noise I'm getting off D02. 
 
Link: https://www.youtube.com/watch?v=NMvwFGDEslY
 
Any thoughts?