I see this is a VERY common problem with these USB sound cards but haven't yet found an explanation or solution.
The crackle occurs when in the DAW (tested in Reaper and Ableton), but the symptoms might differ slightly in how the crackling sounds but both DAWs produce loud, continuous crackling making the card unusable through 2 of the 4 USB ports I have on my laptop (all 4 ports are USB 3.0).
It should be noted that I've used two other USB sound cards on this very laptop without any problems at all, and from all 4 USB ports.
Using an AudioBox USB with the latest drivers on Windows 10 x64 (v18.104.22.168677).
I should also mention that even on the working USB ports, the sound card is overall very capricious: Sometimes when I boot the laptop, the sound card won't work at all. I then need to disconnect it and plug it back in to work.
Thanks in advance!