Sonar Platinum - Focusrite Scarlett ASIO engine keeps stopping

First, make sure you have the latest Focusrite drivers and re-install them. Driver weirdness can happen with Windows updates, and there have been several lately.

Had a lot of issues with my Focusrite 18i20, so much so I gave up and returned it to the store. Turned out it was the 2nd time that unit had been returned. It was clearly an issue with the box being defective. It would just drop out for no reason, SONAR would lose connectivity with it as if I had unplugged the USB cable. Using it outside of SONAR it would cause stuck MIDI notes on soft synths. 
 
Not saying yours is defective but is the Scarlett sharing bandwith with any other USB devices on your system? Assuming it is USB, that can cause issues as well.

Thanks for the info.  I restarted Windows, and re-installed the Focusrite drivers.   I'll see if that fixes things (next time I get a chance to use Sonar).

I don't think it's a hardware issue.  This is because I listen to music on the Scarlett all day long (Foobar, Windows Media Player, VLC, various games, etc.) and have been doing so ever since I got the Scarlett many months ago.  It's only when using Sonar (which is the only application I have which uses the ASIO driver) that I have encountered the problem.
 
Basically, after using Sonar a few minutes, the sound suddenly stops.  It's almost as if the ASIO driver (or the Sonar audio engine) "crashes", but there are no error messages.  When I try to restart playback, I just get crackle.  I also noticed once that there was CPU activity during the dropout, even if playback was stopped.  If I restart Sonar, the sound works again.... until a few minutes later, at which point the sound stops again.
 
Because the problem only arises when using Sonar (which is the only app I use which uses the Focusrite ASIO driver), the problem seems to be software rather than hardware. 
 
I can think of three possibilities:
 
a) The Focusrite ASIO driver is buggy and dropping out on its own (and Sonar is still working fine).
 
b) Sonar's audio engine is buggy and dropping out on its own (and the Focusrite ASIO driver is still working fine).
 
c) There is a conflict between Sonar and the ASIO driver; something is happening in Sonar which causes the ASIO driver to overload or crash (or vice versa), which results in a drop-out.
 
I could eliminate #a and #b by trying to use the ASIO driver and Sonar independently of each other.  I'd have to find another app which uses the ASIO driver (suggestions?), and then also test Sonar with something other than the ASIO driver.  I wish I could get Sonar to use the Focusrite's non-ASIO driver, but if I recall there was an issue with inputs; only the ASIO driver let me use all the channels on the Scarlett.
 
I've been using Sonar with the Scarlett for many months now.  I remember dropouts happening maybe once or twice before, but I don't remember ever having a consistent dropout like this.  So what changed?  Monthly Windows updates, and perhaps a Sonar update (though I'm not sure about that timing; was there a Sonar update after 7 July?)  I can't think of anything else, other than the fact that I'm working on a new project, using Drumlab for the first time.

Isn't this whole thread from Oct 2016 about dropouts with the Scarlett?
http://forum.cakewalk.com/Focusrite-Scarlett-2i4-USB-audio-interface-Dropouts-ASIO-and-other-questions-m3498363.aspx
 
I'd say those problems are still problems.

Some updates on their Beta website as well
http://beta.focusrite.com
 

Craig may be onto something with sample rates changing. The first thing Focusrite tech support will ask you is which sample rate are you using and then they'll caution you about using their device to run Windows sounds in the background. I have an M Audio 2496 on my system that handles everything but SONAR to prevent conflicts. 
 
One thing I did find out with the Scarlett was if I powered it on after Windows booted up it would redo my sound configuration, meaning it would take over everything on my PC whether I had it assigned to the M Audio or not in control panel.
 
As a side note on my desktop I have a PCIe to USB 3.0 card that I use for audio so my USB devices aren't sharing any bandwith.
 
 
 

Actually the beta drivers seem to be older than the current driver version (4.36.4), which is what I have installed.
 
Or are you referring to the beta firmware (version 1.0b1 on 27 April 2017)?
 
Paul, what driver versions and firmware are you using now?
 
 

I've been using Drumlab for the first time (since it was in Komplete 11, which I got recently).  It sounds great, but I notice it uses about 30-35 voices, which seems a bit high for a Komplete Instrument.
 
If I increase the ASIO buffer from 256 to 2048 the latency would go from 5.8ms to 46.4ms, which is pretty horrible for tracking (but okay for mixing).  Are you suggesting doing it as a test only, not a permanent change?

Tripecac
I've been using Drumlab for the first time (since it was in Komplete 11, which I got recently).  It sounds great, but I notice it uses about 30-35 voices, which seems a bit high for a Komplete Instrument.
 
If I increase the ASIO buffer from 256 to 2048 the latency would go from 5.8ms to 46.4ms, which is pretty horrible for tracking (but okay for mixing).  Are you suggesting doing it as a test only, not a permanent change?

Yes for testing only. It will either confirm or rule out it being caused by a plugin or process hogging resources.
 
I did once have a very similar issue which I am pretty certain involved Drumlab and or an effect plugin I had on a bus that drumlab was going through. This could be related. So here's what I did. I firstly did a save as... and on that copy I went through removing plugins (instruments and effects) one by one until I found the culprit, which I am pretty sure was drumlab or the effect. So I kept the midi that was playing drumlab, removed drumlab completely from the project, then inserted a fresh instance of drumlab. THat fixed it for me.

Jengelh71
Tripecac, I have a problem with my 2i2 and just got Sonar professional. Finally Focusrite got back to me and asked me to try a different DAW. I installed the demos of FL Studio and Reaper and the Focusrite worked flawlessly. I started up Sonar again and no go. It just clicks and pops. So apparently there is a problem between focusrite drivers and Sonar. Not sure what to do now because Ive used Sonar for so many years and don't want to get rid of it but I'm not going to keep buying usb audio devices to find they don't work with sonar. I would say try downloading a demo of another DAW and see if it still does it or not.

That doesn't really prove anything as there are lots of people using Focusrite AIs with Sonar without issues and people using Focusrite AIs with other DAWs and having problems. So on your system/Sonar configuration, there's a problem.

I was having some drop out issues with my Focusrite 2i4 for a while there. It happens now and again...sometimes projects corrupt because of it. Anyway so far so good with the newer driver.
 

I just noticed something very strange, and it could just be a coincidence.
 
After I stopped working on my project, I ran my usual backup script, which uses rysync to backup my project files locally and remotely.  I've been using the same script for more than 10 years, but for some reason, for the first time ever, rsync failed, giving me a STATUS_ACCESS_VIOLATION error.  I tried again, as administrator, and got the same error.  It didn't matter if I was rsyncing locally or remotely.
 
I then restarted windows, and tried again.  This time it worked.
 
Could the rsync issue possibly be related to the Sonar/Focusrite issue???  Again, this is the first time I've ever seen rsync fail like that, and the only thing I've done since rebooting earlier (after the BSOD) was use Sonar.