So Windows did a new update last night, and now a project that was nearing completion and was running fine (albeit resource heavy, but running) won't make it through without the audio engine stopping.  I have all my tracks frozen.  Anyone else running into this? 
 
I can't finish mixing and not sure what to do at this point.

Check and make sure Core Parking wasn't enabled by the update and check that Game Mode is off.

Thanks for the advice - despite what others had said, my Game Mode was ON by default.  (I have the Home version, don't know if that makes a difference.)  So now it's off...
 
Can't figure out how to check on Core Parking - everything I'm finding online seems more developer related.
 
Interestingly, I turned off all Fx, and the CPU loads were showing close to 0 on each core - but the hard drive on the processes monitor in Sonar kept glitching red and then it still stopped the Audio Engine after several seconds - so it seems to be something in the Windows update and totally external to Sonar.

I had a Splat crash in the middle of the update. I did lose a couple of audio takes, no big deal on that end. Pain in the rear on the other. Computer appeared to be frozen in the 'don't turn off your computer' screen for quite sometime. Heeded some good advice and just waited. Both computers running normally today, although I did have to reinstall the Wacom pen.

So for the benefit of anyone with the same problem - I THINK I've found a solution.  The Task Scheduler had a bunch of stuff scheduled to check for updates, and repeating every hour.  (Not sure it that happened with the Windows 10 Creator update, or was there before) - but I shut all that off.  I also had to increase my I/O buffer for playback to bigger than it was prior to the Windows update.  At least for now the problem seems to have stopped. (although I'm still holding my breath with every pass...)