X1 Suddenly Stopped Recognizing my Audio Interface

I have been using X1 on and off for several months without any major problems.  But just today, X1 fails to recognize my Scarlett 8i6 Focurite interface and I can’t figure out why. 

• When I open an X1 project, I get the error message “Silent Buses Detected” and Master is listed as the silent bus.
• The output from my Master bus has changed to “None” and selecting any Focusrite options available don’t produce any sound, and they don’t appear to be the correct options anyway.
• If I go to any audio track, the Input has changed to “None” and I cannot find and select the correct Focusrite input, e.g. “Left Focusrite USB Driver Mic 1” no longer exists.
• The physical connections between my PC and my Scarlett 8i6 seem fine and has not changed since it was working just fine the night before.
• Under Edit > Preferences > Audio > Devices, the input and output drivers appear to be correct (although I cannot be sure) and they are all checked
• My Scarlett 8i6 appears to be working fine otherwise, e.g. if I play an mp3 from my computer which inputs to my 8i6, the sound is fine.

 
Any suggestions appreciated!  Thanks.  - Greg

Make sure you are running X1D.
Whether you are running the latest mix control or not try uninstalling mix control and reboot.
 
Then install the latest here and configure mix control:
http://uk.focusrite.com/usb-audio-interfaces/scarlett-8i6/downloads
 
Also try renaming AUD.INI in Sonar (google for details on how to do this).
 
Thanks..

By playing an mp3 you can have that steal your audio drivers. Double check your in ASIO mode and not MME. Every system seems to handle this differently and there is different configurations that will work for one person and not another. 
I disable my on board audio completely. I check share drivers.  This works for me. It's simple and I only need the one system for everything. 
Others use the on board to play Windows sounds and  MP3 and un check share drivers. This involves having the mobo audio output connected to something. You can run the audio out back to your interface or better yet a small mixer you use for this. 
Try them both.  
First check that Sonar is using ASIO mode. 
 

1) Yes. Uninstall and reinstall regardless.
2) Google 'rename AUD.INI' for more details. Search your hard drive as well.

X1D?

Thanks...

Thanks but am still confused on "renaming the aud.ini file” (despite Google search).   I followed the instructions for FINDING the aud.ini file (thanks Ian Ferrin) by opening it up within Sonar.  But this only allows me to editing what is IN the aud.ini file, NOT RENAMING the file name (I assume).  In the meantime, I found my aud.ini file within Windows:   Users > (my name) > AppData > Roaming > Cakewalk > Sonar x1 Producer.  Within that folder can I simply change the name of the “aud.ini” file to something like “aud.ini-old”? 

 
Thanks.  - Greg

I’ve tried all the suggestions above, but nothing works.  I still get absolutely no sound output from Sonar X1.  Uninstalling and reinstalling Scarlett mix control had no effect.  Changing name of aud.ini file had no effect.
What can I try next, as I am totally “dead in the water”, if you know what I mean?
 
Thanks.    - Greg

Sounds frustrating.  For troubleshooting, I'd stop the computer sound in control panel and also try mme/wdm drivers in your focusrite software if it's an option.
 
Well one thing... system restore.  You could try that.
 
Basically though, I don't have a clue.

That's probably all it took. When you rename or delete the Aud.ini file, Sonar generates a new one based on your default settings.

The reboot probably cleared settings from memory and allowed things to load as they should

Excellent news.