Cubase Pro create dropouts too easily - mmcss_test.exe requesting one thread - is enough on normal audio priority

Hi
Sorry for coming back to this topic but something seems really wrong in Cubase audio engine.
it’s beyond reasonable doubt at this point.

I’m so frustrated and upset when I write - this is my third attempt to rewrite in a better descriptive way.

And I emphasize Cubase Pro - since Cubase Elements is not a real problem.
The root of problem is an hourly uptime event in windows - and Cubase Elements run through this just fine - but not Pro.
So back to investigations.

Good part

I’ve been running test applications like Thread Racer - occupying all 8 cores, and running 100% cpu on all - and Cubase is fine - no dropout on recording, just serious bitnoise on playback, but it does not affect recording one bit.
This really good performance - even with audio priority on Normal.

Bad part - how to reproduce

While Cubase Pro is recording - run mmcss_test application found here:
https://helpcenter.steinberg.de/hc/en-us/articles/115000535804-Windows-10-audio-dropouts-on-multi-core-CPU-setups

You have to set Cubase Pro not to release audio driver when loosing focus(Studio Setup).

Test #1(Audio priority Normal):
Just start mmcss_test while Cubase Pro is recording(this create 128 mmcss class threads).

It will create a dropout in Cubase Pro.

Test #2(Audio priority Boost):
Just start mmcss_test while Cubase Pro is recording(this create 128 mmcss class threads).

It will not create a dropout in Cubase Pro.

Test #3(Audio priority Normal):
Make a shortcut to mmcss_test.exe and set a parameter with a blank after “…exe”.
So it looks “,_test.exe 1” - meaning just create on mmcss class thread.

It will create a dropout in Cubase Pro. so you just create one thread, basically initializing mmcss - and Cubase Pro dropout.

Test with other applications

I’ve ran the same tests in Reaper - you can select audio priority - MMCSS Pro Audio Time critical and MMCSS Time Critical.
These both correspond to Cubase Boost and Normal.
Does not create a dropout.

Sonar - I can only MMCSS or not - but it does not create a dropout - no matter what you do.
You can run both Reaper and Sonar with as much as 512 mmcss class threads with mmcss_test - and there is no issue.

You do that with Cubase Pro - and just initializing one mmcss class thread with test program - and Cubase Pro dropout on normal audio priority.
I write Cubase Pro - because it does not happend every time in Cubase Elements 7 or 8.

Comment on my hourly uptime event in my machine

I have some event on hourly uptime in my computer - not sure what yet - but this create dropouts in Cubase Pro - all day long every hour.

I’ve tested on Cubase Elements 7 and 8 - no dropouts on this hourly windows uptime event.
A tiny pop you can hear - but does not affect recording.

Cubase Pro 8.0, 8.5, 9.0 and 9.5 - always dropout on recording while this hourly uptime event.

Sonar and Reaper - not a sign of a pop or recording problem at all - not ever.

I can run video editors like PowerDirector with audio - and does not create dropout or pop or anything.
I can run video players like MPC HC over this event - and no issue.

Final comments and conclusion

Cubase Pro audio engine is overly sensitive?


Thank you for reading.

Bought StudioOne Professional 4 today, and no sign of any hickups like Cubase has on my system.

Not running mmcss_test or my hourly uptime event.

So it’s S1 for a while for me - if this ever is taken care of by Steinberg - or even get a reply to support ticket(two weeks now of silence).