In the first post there is a link to mmscctest.exe this will show if maybe win 10 pro ltsb is the solution. Can you run it and report back?
I will do that. Im not at my studio at the moment but i will absolutely try it maybe tomorrow and report for you how it was for me
Ok guys i have do it jump in the cold water 
upgrade to Core i9-7980XE i have never seen before this performance wow 
For now i donât have any spikes or audio dropout with HT-on Cubase 9.5 is super smooth with Win10 build 1709.
Just amazing Imgur: The magic of the Internet â128 bufferâ
Does this only affect Intel CPUâs? If so, can you update the subject line of this post?
Thanks!
Bryan
I donât see any reason why it would just be with Intel, so no.
Iâm upgraded my Windows 10 Pro to Windows 10 Pro for Workstations edition. In MMCSS test nothing new⌠The same âthreads with MMCSS priority: 32â =((
Asioguard is on or off there?
why would you do that upgrade? what makes you think it would be different?
It was just interesting to see.))
But I do not have problems with the asio performance, any spikes, clips, etcâŚ
LOL, that is always a good reason âŚ
Hi Asioguard âonâ the strange thing is with Asioguard âoffâ Cubase can process âonlyâ 32 threats,with on more then 32.
The best performance i get with 256 buffer and Asioguard âonâ 
Try to disable Hyperthreading in BIOS. Without HT I can run all 40 channels with all RXCs âonâ with 32 samples ASIO buffer and without ASIOGuard.
It seems that the Hyperthreading has a bad effect on the perfomance of the Cubase with a huge amount of processor cores.
I have try this but i dont like it, with HT on, 256 buffer, Asioguard on i get much better performance.
You can max out the CPU to 99% without spikes with this setting.
I have managed to improve my ASIO performance significantly on a 6 cores CPU so I thought I could share my settings in case it could help someone.
A lot of problems came from some Intel and Win10 features that are always trying down-clock the CPU speed to save power consumption, which is totally an ASIO killer. This was causing my ASIO meter to be very unstable, and was causing ASIO drop outs on heavy load.
CPU is a i7-6850K base clock at 3.6Ghz with a Turbo Boost at 3.8Ghz and a Turbo Max at 4.0Ghz. Max memory speed at 2400Mhz.
The key for me was to figure out how to âlockâ the CPU at 4.0Ghz (Turbo Boost Max), all the time, which is the maximum speed of the CPU, without having Win10 or BIOS feature to down-clock the speed of the CPU.
So here all the BIOS settings I had to manually change to make sure the CPU stays at itâs full potential, all the time:
1-Extreme Memory Profile (X.M.P) at Profile 1, to have my RAM running at 2400Mhz instead of the default 2133Mhz
2-Intel Turbo Boost Technology: Enabled, all Default
3-Intel Turbo Boost MAX Technology 3.0: Enabled. (This is what makes my CPU running at the max 4.0Ghz.)
4-Hyper Threading: Enabled. Seems to be ok for me
Now to prevents the CPU to be down clocked or down powered:
5-CPU Enhanced Halt (C1E): Disabled
6-C3 State Support: Disabled
7-C6/C7 State Support: Disabled
8-CPU EIST Function (Enhanced IntelÂŽ Speed Step Technology): Disabled
9-In Windows, make sure to use the High Performance Power Plan. In advanced properties, make sure to have all Processor Power settings at 100%.
Now, after a reboot, my CPU is locked 4.0Ghz all the time, with my RAM running at 2400Mhz.
My ASIO meter is now barely going over 20%, even under heavy load instead of moving back and forth and causing ASIO drop outs.
Hope it helps someone.
Nick
So⌠Iâve switched to x299 i7820x lately (previously riding x99 and i5820k) and⌠turning HT off was the worst case scenario for me. And believe me, it comes from someone who invests heavy money into a DAW rig and spots the difference. First run with audioengine props file was smooth⌠second one not so much so Iâve removed nvidia drivers (from nvidia not from microsoft update) - i love my gtx card (1060) but since 5XX series they tend to have problem with latency spikes and eco/power saving mode. Just google it
Iâve updated my Cubase to 9.5 and everything went smooth. I brought back HT, and there is a huge difference for me (in speed and responsiveness), while running Windows 10 Pro. But still⌠only 14 logical cores 
Sucker am I? 
Anyway⌠I hold back with updating Meltdown/Spectre patches (come on, hack me if u can for a next 23 days) and Iâm little dissapointed about Cubase performance barrier⌠yeah, you can blame Microsoft too but I think, Steinbergsâs team relies too much on Windows ânot so known or documentedâ restrictions (membah stupid aero mode requirement?).
Just my 5 centsâŚ
Try modifying that audioengine properties file to set 28 threads instead of 14. I did this on my 7940X and it is using all of my logical cores without a hiccup. I think Steinberg got their wires crossed on that thing, it sets the total number of Cubase threads (not how many cores to run 2 threads on). When I used the default, only 14 logical cores were used and I knew that meant only half of my physical cores because it was the first half instead of every other one. Maybe without having that file at all Cubase will try to spawn 2 threads for every logical core it finds, but whatever value gets configured in that file sets a strict thread count limit.
Side note: I sold my Xeon box and switched to 7940X specifically because of this limitation. No reason to be able to expand to 24 physical/48 logical cores in the future when Win 10 maxes out at 28 logical cores for DAW. I really hope Microsoft gets this sorted out now that we have enthusiast chips on the market that can exceed this limit.
omniphonixâŚhow do you modifying audioengine? Could you please describe for me how to do itâŚi also have a 7820x and would like to know how to use my system to the max in cubase.
this means file âaudioengine.propertiesâ you can found /download from there to install inside given steinberg paths
Default setting of this file by steinberg:
audioengine.threads.max=14
Iâve recently built out the following system:
Proc: Intel Core i9-7900X Skylake X 10-Core
Motherboard: ASROCK X299 Taichi
Ram: CORSAIR Vengeance LPX 32GB (4 x 8GB) DDR4 2666
Cooler: Noctua NH-D15
OS Drive: SAMSUNG 960 PRO M.2 512GB NVMe
Media Drive: SAMSUNG 960 PRO M.2 1TB NVMe
Samples Drive: SAMSUNG 960 PRO M.2 2TB NVMe
Video Card: Gigabyte GeForce GT 1030 2GB Silent Low Profile
Screen: LG - 34UC79G-B 34.0" 2560x1080
Case: be quiet! PURE BASE 600 - Black
Power Supply: be quiet! - Dark Power Pro 11 650W 80+ Platinum
Software: Cubase Pro 9.5, Native Instruments Komplete 11 Ultimate
Audio Interface: RME Fireface UFX+
On initial setup, the Cubase 9.5 demo song was playing with no issues and plenty of headroom down to a buffer of 32 samples. Recording, however, was not working down to 32 samples. Cracks, dropouts, etc. I didnât change anything else (HT still on) and dropped in the audioengine.properties file with no changes. With that change, recording with a 32 sample buffer was fine. A 64 sample buffer didnât bother me and I did a jam session with Guitar Rig for over an hour without a single hiccup.
This is going to be a great system, I think!
Guys look @ this IMG 0685 - Sendvid
The key is never go under 128 samples with HT On.
128-256 Buffer + HT on + Asioguard = best performance.
HT needs minimum 128 Buffer or you get a popcorn machine