I just received my PowerDac V2 yesterday after forgetting i ordered it a month ago direction from HPToy...i almost screamed when i finally got it working after three hours of mistakenly trying to get it to drive my desktop system (no instructions in box , all lettering in chinese), but study of the HPToy site revealed pictures of how to set it up with smartphone and more operating info. The thing really is an audio miracle! i ran a balanced cable out to my MicroZotl tube headphone amp, using it as a preamp, and the Fostex Mohoghany X00 headphones suddenly woke up with a sound i had never imagined it had in them. voices were floating in the middle of the stage, EDM sounded like i had my head inside a subwoofer, textures were sublime and awesome,, in short, best 50$ ive ever spent hands down. one caveat: turns out running an audioquest jitter reduction filter at the end of my high quality usb cable made a big different in volume and clarity. not sure why, but it works. anyway..go for it! asap!!!