Hello,
when I use all instruments Abbey Road Drummer with Sonar X3c they crash the audio engine. This happens, when I change the mix from one to another type of drummer sound. This problem is not noticeable with Sonar X2.
Have you a idea?
 

I have the same problem, intermittently with Izotope Ozone 5 when changing pre-sets while the track is playing.  I've noticed it on other VST's also.   Never had the problem in previous versions of Sonar.

I do not have the separate Abbey Road Drummer product.  I only have the Abbey Road 60's Drummer library for Kontakt 5, that I got with Komplete 8 Ultimate.
 
Using that, I have no issues switching between kits.
 
Sorry I cannot provide additional testing or information - hopefully someone with that separate product can post on their experiences with it in X3c.
 
Bob Bone
 

I've had this issue, but only when my latency is set to it's lowest. It didn't crash SONAR but it seriously hung the program for a while. This was with an Edirol UA 101 sample buffer of 96 2.2 ms of latency. Once I bumped it up a bit to 3.3 Kontakt behaved fine. Remember those kits use a LOT of RAM and the newer ones have all those extra effects that munch CPU. 

I use 128 for my ASIO Buffer Size and have input and output latency values of 4.7 milliseconds each way, for a total roundtrip of 9.3 ms, and I the application never hangs, nor do I ever have crackles/pops/dropouts and such.  (sample rate is set top 48 k, as well)
 
Hope that helps, 
 
Bob Bone

No issue here (I tested this yesterday). Please update the drivers for your audio interface and check the windows event viewer for more info.

The on-board mixer in the Native Instruments "Drummer" libraries is a real CPU-hog, and it seems to affect the first core rather than spreading the load. The Kontakt options let you specify multiprocessor support (Options->Engine->Multiprocessor support) and if so, how many cores to use, but I haven't seen much difference. There have been quite a few discussions about this on the Native Instruments forums and I've seen people recommend both turning off multiprocessor support and turning it on with various numbers of cores selected. So it might be worth experimenting with this to see if it has any effect. Please note that when you change the processor options in the Kontakt VST, you have to restart Sonar for the change to take effect. A bit of a pain I know. 
 
I don't know why the Drummer mixer effects use so much CPU. I have pretty much all of those effects as standalones (Transient Master, Solid EQ, Solid Bus Comp etc) and I can use way more instances of them than you'd have in the Drummer libraries, with no CPU overload whatsoever. 
 
I'm not 100% that this is the root of your problem, but the chances are good. If messing with the processor options doesn't work then all I can suggest is that you ditch the on-board mixer altogether (select the INIT mixer option), route all of the drums to separate tracks in Sonar (plenty of tutorials online which teach you how to do this) and do the processing yourself in the DAW. 

hello,
For information, the problem has been reproduced among developers, NI will try to correct the problem.

BlackBird67
hello,
For information, the problem has been reproduced among developers, NI will try to correct the problem.

Can you point the source of this information please?
 

Native Instruments