My RME UCX in Asio in Windows 10 is making tons of popping when opening and closing projects or Preferences.
 
Sometimes I have to close and re-open the project.

Make sure you have the latest drivers installed or reinstall them.  Sometimes things go haywire with an OS update.  

I did a clean install of Windows 10. By this I mean I formatted the OS Drive and installed from scratch. Nothing left of Windows 8.1 at all.
 
Then I went and downloaded the latest drivers from RME which say they are Windows 10 compliant.
 
It does 'work' but hitting stop during playback causes a pop. Doing anything really. I'm not sure what the problem is. I'm considering borrowing one of these Firewire cables and re-testing with that to see if my issue goes away.
 
Noel? You're on Windows 10. How's your UFX working?

https://www.forum.rme-audio.de/viewtopic.php?id=22501
 
I posted here to the RME Forum.

I'm interested to hear if you resolve this issue, myself I think Ill wait a while to update to Win10 until MS has more free beta testing done by users (that should be done themselves before releasing) and when I upgrade my PC. I'm still coming to terms with UFX in Win7 and similar rice crispy (snap crackle pop) issues since upgrading to the UFX from an M-audio PCI interface card, and what I still think are USB limitations, perhaps coupled with my older PC. (Intel Core - 4 core 2.3 GHz).

@John Egan
You should not be having problems with your UFX in windows 7. It is more likely you need to raise your buffers or that you have drivers causing deferred procedure call latency that is too high. Have you tried latency Mon by resplendance?

I am continuing to have lots of popping in Windows 10.

Anyone else using an RME on Windows 10 with sonar?

Double

Out of curiosity, have you tried the USB drivers?  
 
It is most likely not a cable issue, but a Windows driver one.  RME hasn't had any driver updates since 10 was released, likely they are waiting on more reports like this.  

I have only tried USB. I don't actually own the FireWire cable required.

I'm not dead in the water either. It functions, but not brilliantly. Only sonar is having a problem so far. All other apps work fine with it.

I'm using Asio.

Just curious, was your Win 10 upgrade to Pro or Home?