I have had this wonderfully musical dac modified by Sean Jacobs at Custom Hifi Cables. The onboard psu has been replaced with an offboard psu using a custom made torroidal transformer from Canterbury Windings and Mundorf caps. The dac chip is now powered by the psu instead of the noisy usb supply. Sean also replaced the dac output caps for Jupiter copper foil. The dac is NOS and is single ended only, 230v. Collection is preferred as the psu is heavy, but no problem to post at extra cost.