In fact it was a dual setup system, that I was doing for our customer, that have bought your Roon license through us. He was greatly satisfied with Roon and our audio card. It was under a Windows 10. One time I visited him with another computer to show him how much improvement he will get with two computers – server and core setup. Another great results, he went for that setup. He gave me some time to reinstall everything as he went to a holiday. As I reckon, linux Is a much better choice for audio, so I wanted to do his Roon Core computer with a Ubuntu. Then I have encountered that problem. As I have run out of time, I came back to Windows. I don’t want to disappoint him with another waiting time, but for that problem I will try to take one of our computers at work and install ubuntu, our card and show that problem. Basically it doesn’t matter what dac I am using and what hardware. Problem is with OS I think. To clarify, I am using Pink Faun Audio Bridge as a PCI sound card. I will reach out as soon as possible with more info. Thanks for response!