More crashes in the last few days than in the past 5 years! [Solved]

Sonar, as far back as I can remember never gave me major problems like audio engine dropouts and program closing prematurely.
I don't even know where to start.  Tonight I created a new project from my normal blank template.  I had just two plugins open, Superior Drummer 3, and Kontakt with the new Orange Tree Samples' Evolution Rock Standard (guitar). With no efx on any tracks or busses.
It's a new Sonar build, a new version of Superior Drummer, and a new guitar sampler for Kontakt.  And once again, I got the Audio engine dropout, followed by Kontakt freezing, and then Sonar closing.  When it happened, I believe I was going through various presets of the Evolution Rock guitar, and playing them a little at a time.

In my previous post, I was having issues with the render operation (to a stereo wav file) stopping halfway through.  But now the problems seem to be getting worse, with the simplest of projects with just a drum track laid down, and me playing along on the Kontakt player....not even recording anything yet.

I've been having issues with Saffire MixControl software changing ASIO Buffer sizes on it's own.  So I contacted Focusrite and he gave me a beta driver to try and fix that issue.  I have a Saffire Pro 24 audio interface connected via Firewire.
I usually have the ASIO Buffer set at 512.  And my project settings are currently set to 24 bit/48,000  (I used to have it set at 24 bit/44,000)

So I don't know, these Audio Engine dropouts and program crashes could be a dozen different things.  I thought I might have been overloading my DAW.  But there should be no reason for this to be happening with a new project with just two plugins open.
It could be a driver (but from what software/plugin?), it could be a hardware problem, my interface, a hard drive?   But everything else on my Windows 10 64-bit machine (32 GB ram) is running fine.   I'm totally at a loss. 

And it couldn't have come at a worse time, I was just preparing to launch a local advertising campaign for my recording studio/producer work.  I can't have clients coming over to a DAW that keeps crashing. 
And this is the worst kind of problem, it's intermittent and occurs over various configurations.

Where do I start?

I had the same thing happen to a lesser degree after the Windows update of a couple days ago. I installed the latest Sonar version, and all was well. I hope the fix is equally simple for you!

Thanks for the suggestions.  I already have the latest Sonar Platinum release.  In fact I was thinking of rolling back to the previous release to see if that might help.
I'll also try the other suggestions and I'll keep the full system Windows restore as my last option.
But first I'm going to try the Latency Monitor and see what I can find out.

Thanks again.  I'll keep trying different things, but as I said this problem is going to be hard to track down because of it's intermittent nature.

I'll chime in because you mention Focusrite.
I don't have much experience with Firewire (I've never used it), but you might consider trying USB?
I was having the same problem as Tripecac on this thread where (for me) since the Windows 10 Creators Update, audio was dropping out every 45 seconds or so (in everything, YouTube, MP3s, etc.).
Since the Creators Update Windows 10 seems to have an issue running the 2i4 (which is USB 2.0) through a USB 3.0 connection. All of my external connections on my PC case are USB 3.0, so I had to run the Focusrite 2i4 directly to the USB 2.0 pins on the motherboard and the audio dropout issue in Windows was fixed instantly.
 
Before that, about a year ago, Focusrite also sent me a driver to get my Focusrite to work in Windows 10, just before they updated to their latest USB driver version.
 
When you say new build, I wonder if you have recently upgraded to Windows 10?
Please note that the Windows 10 Fall Creators Update is due in just 2 days on the 17th of this month, so it might be good to do a fresh ISO install of that when it's available, in which case holding off until then could be a good thing.. 

My 2 cents worth post was retrieved from the automated spam and inserted before your post.

Sorry. I replied to your post a while ago but it was automatically deleted by Akismet (which is a forum spam service which removes posts if the user edits them too many times). I asked the admin to retrieve it and post it back in this thread, and he kindly did so, but it appeared before your last post, not after. Just in case you didn't see that post.
(I also sent you a PM about this at the time, in case it could help.)

GjB
I'll chime in because you mention Focusrite.
I don't have much experience with Firewire (I've never used it), but you might consider trying USB?
I was having the same problem as Tripecac on this thread where (for me) since the Windows 10 Creators Update, audio was dropping out every 45 seconds or so (in everything, YouTube, MP3s, etc.).
Since the Creators Update Windows 10 seems to have an issue running the 2i4 (which is USB 2.0) through a USB 3.0 connection. All of my external connections on my PC case are USB 3.0, so I had to run the Focusrite 2i4 directly to the USB 2.0 pins on the motherboard and the audio dropout issue in Windows was fixed instantly.
 
Before that, about a year ago, Focusrite also sent me a driver to get my Focusrite to work in Windows 10, just before they updated to their latest USB driver version.
 
When you say new build, I wonder if you have recently upgraded to Windows 10?
Please note that the Windows 10 Fall Creators Update is due in just 2 days on the 17th of this month, so it might be good to do a fresh ISO install of that when it's available, in which case holding off until then could be a good thing.. 

Hi, I got your PM.  I do have another Focusrite audio interface (Scarlett 2i2) which uses a USB 2.0 connection instead of Firewire.  The reason I'm using the interface with a Firewire connection is because I read that Firewire offers faster speeds than a USB 2.0 connection.  I never had any problems using it, so maybe I'll try that again to see if it works any better. Thanks for the suggestion.

So far, today, I've still had no issues yet.  And I've been pushing it pretty hard.  So I'm not sure what's causing the problems I've been having over the past couple of weeks.

Rob[atSound-Rehab]
Any hints that your problems may be project specific? It's strange that you can push it one day but not the other ...

No, I went back to the same project as yesterday, and tried to do the exact same things I was doing before and when it crashed.  That's what makes me think it's a driver issue within Windows, my plugins, or my hardware.
It could have been something as simple as Bitdefender doing a virus scan (which I'm now turning off when I run Sonar).  But until the next problem happens, I'm just guessing.

I just had another Audio Engine stoppage.  Again, the project was small and simple.  Three VSTi's active: Superior Drums 3, Orange Tree Samples guitar, and Scarbee Bass (which is what I was playing at the time). No efx inserted anywhere.

I decided to look at my Windows sound configuration and noticed the computer's digital audio (S/PDIF) High Definition device was reinstalled again (after I uninstalled it on 10/5/17).  If you look at the screenshot, you'll see that this device was reinstalled again 4 days ago and enabled, "Ready" (under the Playback tab). But it's not my default device, which is my Saffire Audio device. 

I disabled it once again just now.  Is there any chance that THIS could be causing the Audio Engine to stop?

I hope it works for you. I have never uninstalled a driver instead opting to disable it. Uninstalling a driver may cause Windows to re-enable it should it decide to update the missing driver.

I wouldn't do anything in the registry.
I also wouldn't worry about things appearing in the list. Just make sure that the one you want is the default and it should be OK. My above instructions are just to stop Windows reinstalling manufacturers' drivers over the ones you choose to manually install.
 
So for example if Focusrite or someone gave you a driver, or you use an older driver which works perfectly, then Windows won't try to replace it with something else.
 
Edit: Do what Scook says below, too.

Okay thanks again for all the advice, I really do appreciate it.

  But I'm sort of back where I started from.  After disabling everything I don't use, after rebooting my PC, I'm still getting one of the HD Audio drivers from the computer enabling itself again.
And the Saffire MixControl software is still changing ASIO buffer size on it's own. 
I've also noticed that Sonar takes a very long time to load a project, even a small one. Sometimes taking up to a minute or two to open. (when normally it would only take a few seconds)

And reading through many forum posts here, as well as Googling trying to find some answers, I'm finding an endless amount of information that often contradicts each other.  So I'm just a bit frustrated.
Especially after Sonar has been virtually rock solid for me, for so many years.  And now when I want to start working professionally with it, it's become unreliable.  I was nervous enough worrying about how well I can work with paying clients (based on just my own skills and talent), now I've got this whole new level of uncertainty which seems like it's totally out of my control.  *sigh*

The Windows 10 Fall Creators Update is going to start trickling out in 2 days' time on the 17th.
So when the ISO of that becomes available, if you want the latest version of Windows 10, then you can do a fresh Windows 10 install and start from scratch. That's what I plan to do, and millions of other people I expect.

GjB
The Windows 10 Fall Creators Update is going to start trickling out in 2 days' time on the 17th.
So when the ISO of that becomes available, if you want the latest version of Windows 10, then you can do a fresh Windows 10 install and start from scratch. That's what I plan to do, and millions of other people I expect.

I've had to do fresh Windows installs in the past.  Even with all my DAW software backed up on an external hard drive, reinstalling all my programs is the biggest PITA I've ever had to deal with.  Doing a fresh Windows install, removes all your personal data and software, and even if I have everything else backed up, installing hundreds of programs, plugins, and efx software, INCLUDING having to get much of that software re-authorized, is a project that takes several days!  Often I can't just re-authorize software automatically.  I have to contact the software company, either by phone or email, and wait for them to help me reauthorize it.

It's by far, a very LAST RESORT.  Starting from scratch, after having to do that (about 6 or 7 times already) whenever I get a new computer, or if I have a major hardware failure, is definitely not something I would want to do again, except when there's no other alternatives.   Even when I mirror/ghost copied the complete hard drive, specifically meant for easy transfer from one drive to another.  I still ended up having to manually reinstall and reauthorize much of the software that I was transferring.