The main PSU board was replaced by Schiit after it was sent back a second time when it died (transformer dislodged.) It is already common knowledge that a switching PSU wallwart is pure garbage to use, especially for USB power implementation, Where it is known to be uber sensitive to improve with clean power. Look at the size of the wallwart. I know schiit says its not a switching PSU, but it is an "AC" out PSU. No DC filtering then. Just because the unit is branded "Schiit", does not make them immune to these problems. You can't use a cheapo power supply and just expect to achieve same performance as a good linear power supply. Or it is sensitive to it's garbage wallwart "RF" that you think is "ok" to use because it came with the Eitr. Try a better power supply.