I buy used device. Tested, after come to home connect and in 1-2 min device stop working. (no light) So I bought PSU and replace, now unit:
• After connected power ≈1sec I see green light after always "stable" yellow color and after ≈20sec fun switch to max rpm.
• If I press reset button and connect power, ≈1sec green and after blinking yellow (all time I push this button).
No device in AirPort Utility, no light on connected Ethernet cables, but USB power is ≈5V.