Manufacturer is admitting there might be no audible improvements as well, so what Wyrd does?
- Ensures a very clean +5V for the USB transport chip (if the DAC/device really needs it).
- Provides galvanic isolation from power (mains) through the built-in AC-AC transformer.
I'm pretty sure there should be somewhere on this planet a device that will actually benefit of such a clean +5V power. After all, on eBay a linear PSU of a decent quality is over 20 USD and a transformer is about 15 USD, so finding Wyrd at about 50 USD (like I found) might worth buying. Never know when in need for a +5V to some project.
At least it does something measurable to the USB power, even if the sound doesn't gets changed, not like expensive 16A gold-plated power cables used to power 0.1A DACs.