I have a HP ProBook 4520s with SSD drive and Windows 7 64 Bit. The device is freshly installed with the latest Windows updates.
I also considered tips from https://support.presonus.com/hc/en-us/articles/210046153-Optimizing-Your-Computer-for-Audio-Windows-Vista-Windows-7
When I attach my AudioBox 1818 VSL interface and e.g. just play a WAV file in VLC Media Player I get a lot of crackling noise during playback.
If I play the same WAV file with the same audio interface and USB cable but attached to another Windows 7 x64 workstation nearby (exactly the same setup, just plug the USB cable to the other machine) I don't have any problems - the crackles are gone.
I'm using firmware version 1.18 and driver version 18.104.22.16853. ASIO buffer size is set to 2k on both machines.
Any ideas how to diagnose that further?