Hi all,
 
I justed wanted to check with the unlucky few who suffered from the "loud click & DC output" issue that have plagued some of us. Do you still experience the problem? I do indeed and while I was able to get by in previous projects by just cycling either the engine or the FX button until Sonar worked fine again, that´s not working with the current project so I need to find a solution. I´ve contacted support about this, let´s see what they can do about it.
 
 
Some detailed information about my problem:
 
Quite often when I play a project, there´s a loud CLICK and then silence. The project keeps playing and the CPU meters look normal but no sound is being output. However, when this occurs, the VU meters on the master bus of Sonar is constantly peaking and the relevant meters in RME TotalFX do the same.

If I click "stop" and try to play the project again, the problem sometimes goes away. However, often stopping does not help and I have to restart Sonar or do something hardware-related such as changing ASIO buffer in order to get the sound working again but these fixes are always temporary.

This problem is more likely to occur in a crowded project with lot´s of plugins though it might happen in lighter projects as well. Typical plugins that would trigger this issue is Melodyne, Vocoders and sometimes ProChannel plugins. However, removing/disabling these plugins without restarting Sonar does not make the problem go away.


Observations:

* I have had it on two different computers, Win7 AMD 965 BE and Win10 64bit Xeon E3-1270 HP Z210 (both clean installs).
* I have experienced the problem on both a RME Babyface and a cheap $5 USB audio interface.
* If I play audio from outside Sonar when I´m having this issue, the audio is audible but severly distorted. If I disable the Sonar engine, audio outside Sonar is working fine.
* The problem is very random.
* It seems to happen regardless of which project I´m working on though the problem does happen more often on heavier projects.
* ASIO / WDM / WASAPI does not make a difference
* Audio buffer size does not make a difference
* If I export audio during this condition, the exported mp3 will contain nothing but DC.
* I have tried different USB ports & cables.
* All CPU / USB power management features / throttling are disabled.
* I have tried disabling/enabling CPU hyperthread / turbo.
* All drivers are updated to latest versions
* Disabling GPU did not improve anything.

What to do? I´m getting desperate as this is really blocking my workflow.
 
Hardware specifications:
HP Z210 Workstation, Xeon E3-1270, 16GB, Samsung 850 EVO SSD, Quadro 2000 GPU
 
 
Screenshot:

Any stretched audio in the project? Try disabling 64-bit Double Precision Engine in preferences; it can have issues with stretched audio, and possibly some plugins.

I'm seeing something very close to this when using some Kontakt instruments.
 
New blank project, add Kontakt 5.6.1 with one midi track and one output track.  Load a short MIDI loop (doesn't matter what) and turn it into a groove clip and fill a few bars worth and set the project to loop on that.   Inside Kontakt load one of the newer Sample Logic instruments.  I've reproduce it with Morphestra 2, Cinemorphx, and Cinematic Guitars Organic Atmospheres.  Any of the "new style" Sample Logic instruments (older ones don't seem to have this problem).  Inside the instrument use its native preset browser and select the first preset.  Start SONAR's transport and have it play the loop you made/loaded in.  Then using the next patch arrow in the Sample Logic preset window to switch through the presets while the MIDI loop plays.  At some point SONAR makes a loud clicking/pop sound.  The output on the Kontakt instrument channel becomes pegged.  The output on the Master channel becomes pegged.  Inside Kontakt its meter shows nothing is playing.  The MIDI track keeps playing but no new notes are played and there is no more output. 
 
I have the 64-bit Double Precision Engine off.  I've tried all the multi-threading options (in both SONAR and Kontakt).  It reproduces very easily for me at the same patch/preset every time if I use the same MIDI clip.  If I make up something new, the preset it freaks out on changes but it still happens sooner or later.  If I jump to that preset (and not go through the ones just before it) everything works fine.  Sometimes using Kontakt's reset button helps, but not always.  This doesn't reproduce in Reaper, it appears to be a SONAR thing.  Though it certainly could be Kontakt's fault.
 
If I have T-Racks Bus Compressor on the master output when this happens SONAR crashes inside the T-Racks plugin (it doesn't like the weird fully pegged DC audio I guess).  Without the plugin there is no crash.  SONAR acts just like lv455 describes though when I don't have the bus compressor on the master output.  At first I thought this was a T-Racks bug, but I'm not so sure now give what it does with just plain Kontakt and nothing else.
 
I'm running SONAR 22.9.2 Build 42 (2016.09) on Win 7-64 bit with Kontakt 5.6.1(R48).  I don't believe this is actually a Kontakt or T-Racks problem though, those are just the easiest way for me to reproduce the problem.  I tried a lot of different Kontakt instruments but only could get it to happen easily/quickly with the Sample Logic ones.
 
Sadly I haven't found any work around or ways to avoid this, yet.

I've had this problem for many months. It's frustrating and also potentially dangerous if it's sending DC to speakers.
 
I haven't been able to find a reproducible recipe. I used to think it was using Ozone on the master bus. My current thinking is that it is the Sonitus reverb plugin (which I use a lot) on a bus. But it may simply be a gnarly problem with plugins in general. I've tried turning off the 64 bit engine to no avail.
 
Is Sonitus reverb a common factor here, or are folks seeing the problem without it?
 
Sometimes exporting a project to a wav file simply gives a file full of the maximum negative 16 bit integer (i.e. negative DC). This happened recently three times in a row! But this is just Ozone doing it's limiting thing. Without Ozone, I think there are infinities being created. If I use Span, it tells me the RMS is Inf.
 
There is definitely a dangerous ghost in the machine here that I hope someone can find a reproducible recipe for - then Noel will be able to track it down.
 
Cheers, Peter.
 

My reproducible case uses no audio effect plugins.  I start with a completely blank project.  So I'm pretty sure it's not (directly) a audio effect plugin causing this.  Last night while writing the above message I reproduced this a few times and on one attempt got the garbled white-noise constantly increasing in volume effect.  I had to turn off SONARs audio engine to stop it -- usually it just pegs the VU meter but other than the inital pop doesn't make any noise.  I hadn't seen this bug before the 2016.09 release, not sure if rolling back is worth the work though.   Given how tricky this is to reproduce I have no hope it will be fixed anytime soon.

I've submitted the T-Racks crash (which is because of the audio engine doing the pegging and not directly a T-Racks problem) as CWBRN-55672 not sure it will help though, they will look at it and blame the plugin and ignore the SONAR audio engine being crazed.
 

lv455
* If I play audio from outside Sonar when I´m having this issue, the audio is audible but severly distorted. If I disable the Sonar engine, audio outside Sonar is working fine.

This is a really interesting observation. I get this too (along with everything else you mention).
However, if I enable "Share drivers with other programs", the audio outside Sonar sounds OK while Sonar has this issue.
 
What does this tell us about the problem?
 
Cheers, Peter.

Did a rollback to 2016.08, sadly it happens there too.  Didn't try going further back.
 

It tells me OS management has corrupted ,or is tying things oddly together, causing the glitches...and IRQ and or interuptions of cpu and or Data transmittion is being hogged by unknown services running at times of heavy use, or exclusive use of resources.
 
I had cpu issues back in the day...Just open up sonar..and load nothing, do nothing..and watch the cpu metering and drive meters...for a bit of time..mostly a 20min run of nothing being done or more.
 
Is this showing usage beyond reason?...if the cpu meter suddenly spikes into the red?...can you capture a screenshot? save of ..and get the clocked time, and go into event viewer and read out what may be logged,and seek out what causes?.....i believe I did try to do this with MS tech support , costing a yearly payment plan to get someone who would...Yet each remote viewing viewer trying to resolve, would not go into event viewer at all...(until forced by me saying) He did nothing but sell me windows 8.1 to solve, which did nothing to solve for.....
 
Seek out the time in the screen shots, when this occurs, in event viewer, and make logs and or screen shots of what is running when these events occur...if possible.?.
 
Got to be quick...Got stay focused...but I did do...in a old posting.
 
So, is this routed to the Wonderful Sonar and bad code of theirs?....No, I do not believe it is.
I believe it is the OS running apps or services causing the glitches....and or auto updates checking constantly for ...and or data tranmittion and receiving of...when you or the users are working on, or in a project, that wants full control of resources...yet something is running causing loss of.
 
Any hoot...read some of the other postings on oddity of audio hickups and bad noise from high ended audio external devices...
It is not uncommon...as it is being witnessed by some more and more.
 
And jumping back to older iso or version does not solve for.
 
So, tied up, bound down to troubles, and system under arrest?..and now resolution?....
 
Turn it off...pick up a instrument, and play !..Go out side, and sow seeds...be as good as good can be...be free from the troubles....And walk in the land of the living!...smile...and say...Life is good or very Good when doing the service in the Garden with a song well played for free, with the good intent for the living things all around waiting for you to do that good service!...and if you make a bad note, You know you can correct it with practice, and be forgiven the wasted time, not doing any, under idol control!
 
 
Regards!...and best wishes.
 
Sir Les
 
 
 
 

Does your project(s) start at measure 1?