After some investigation it seems to me like this is a Sonar problem. If I play a just a simple project with a few audio tracks, Superior Drummer and Halion Sonic 3(HS3)  in 96/24 mode I get a lot of clicks, crackeling and sound dropouts. Some presets worse than others. If muting HS3 in project and play the same preset on standalone version of HS3 while Sonar project is playing - no problems. Changing latency on sound card (RME FF800) to maximum does not change anything. CPU load around 25%. Memory 50%. Playing around with different performance settings in both Sonar and HS3 without results. Also trided HS3 on demoversions of studio one and Cubase without these problems. Anyone had similar problems and solved them?


Thanks!
 
Computer Intel i7 960 - Sound card RME Fireface 800

Have you tried the standard stuff?  Update drivers.  Try 44.1 khz 

I had exactly the same issue with the Antares AVOX 4 plugins.
 
It turned out to be a VST3 compatibility issue between SONAR / AVOX. Switching to the VST2 plugins solved all my issues.
 
Might be worth renaming the VST3 plugin dll to .dll.old, and see if the VST2 version works better?
 
M.

Were you ever able to run this combo successfully, or is this your first time trying?
 
If you're using VST3, then do what the other poster suggested and switch to VST2.

Thanks for the suggestions!
Did some more digging. Found out that the more plugins in the project the worse it gets. So it's not just Halion Sonics fault but there are some presets in HS that uses quite a lot more cpu than others and just "kills" the project.
Using 44.1 helps but with bigger projects the symptoms will be there too. Switched to 96/24 from 44.1/24 not long ago and the problem got much worse. Noises an dropouts sounds like typical processor overload/latency problems but the strange thing is processors (4-core 8 threads) showing little load(25%) and maxing latency does not help. Switching from vst3 to vst2 did not help either. Maybe there is a bottleneck somewhere else on my motherboard that does not show on the meters. Win 10 installs all the drivers for it but there are no official win 10 drivers from the manufacturer. Computer may not be powerful enough for the way Sonar handles plugins? Did not have these problems when the PC was new but there's been a lot of newer versions of both Sonar and plugins since then so i guess the hardware at some point needs to keep up. 
Sound card and video card drivers are up to date (even tried older drivers), tried different soundcard - same behaviour. Only SSD disks, 12GB RAM. Ti-FireWire card. Everything seems to me to be correct according to common known optimisations for DAW use. Could always jump ship and switch to another DAW (it's probably the right time) but starting all over again will probably kill the creativity for a long time spending most of the time fiddeling around trying to learn something completely new... Used Sonar for at least a decade now and know where everything is and how to get things done :-) 
 
/F

Please check DPC on drivers using LatencyMon utility.

Just above 1000μs, in the yellow sone saying "This machine should be able to handle real-time streaming of audio and/or video data without drop-outs." Already tried to disable different hardware in device manager without affecting latency. (Remeber PC was at 500μs when new) What's strange is what I mentioned in my first post, if I run Halion Sonic outside Sonar and play the same sounds while the Sonar project is running, the problem is not there. So seems like using synth as VST in sonar puts a different kind of load on the system than as stand alone outside Sonar.
 
/F

Problem solved. As I feared the computer wasn't powerful enough. Had to build me a new one. 
 
Thanks for all the input!
 
/F