Posting to see if anyone has any input (no pun intended) on the subject of the C2500 USB section. I have had this unit since early 2014 and it's been sonic heaven to say the least. Everything sounds incredible; phono, analog and digital sources. There was a period of time a couple of years ago that the usb input was quirky and I'd have to power cycle to get it working. I tried another cable and it was fine ever since. Until a couple of weeks ago that is. I then tried everything from (2) other Mac computers, a windows machine, new, decent quality USB cables including a brand new Audioquest Cinnamon and a Wire World Starlight 7. Also I've reset the machine. I should also mention that the other digital inputs work perfectly. It's an awesome sounding machine. What else could I be missing? I certainly hope it's something simple but am getting that nervous feeling about it.