Just a little heads up, since I see these questions get asked a lot.
The DAC works fine with my phone (LG G6) and previous phone (Samsung S5), ans of course my PCs with Windows 10. I use both Usb-C ans Usb-B ports.
I use the DAC alone with Pioneer M531 (32 Ohms, I believe) and Sennheisee HD 600 (300 Ohms). Both work fine. I do not even need to switch to high gain for sufficient volume.
Living in Norway, I had to pay customs, though. Still...