After 2 years my uDAC certificate has reached its expiration date. It is hot and strong distorted when played through headphones / line-out. Whether it is related to the quality of the potentiometer 'crunches, grinds and scratches'? Too bad, because the sound quality I was very satisfied. But I mean that electronic devices do not have to be a total loss after such a short time - especially if the manufacturer advertises a certain quality standard. Therefore my devaluation of the product