I had the same problem with my UFX. I've written to the rme service who eventually told me to ship the card to a repair center. The repaur center told me to ship it to a music store wich will ship it to them. Minimal cost 15-$ dollarss just to diagnose. Plus the fixing plus the shipping plus labour you average a price of 600$. So I've made my research on forums and found out that a lot of people have the same issue and there is some solutions. I also have a rme firewire 800 wich I changed the power suplly a couple years ago (what another power supply problem?). So I placed that PS in my UFX and BINGO! I think that in most of cases you see everything moving on your UFX but no sound out, try the power supply. They sale the unit for about 150 dollars on rme site wich is way less than a new UFX card. But its a shame that RME won't recognize they have a design problem with their power supply. They all will eventually break!!! (I've know to much persons who had the same problem) I've talk to a former representative in canada and he told me that RME knows about this issue but they will just pretend they don't. Don't get me wrong, I love my UFX more then my FW800 and more than a lot of sound card on the market. But when you pay more than 2k for a soundcard it would be nice they would offer a replacement card for way less money, knowing that its their fault. Especially when we all know that those power supply costs a couple of box to broduce. Good luck all.