Audio Glitches in Windows 11 HW 7

I get occasional audio glitches. I've been using Oakland AS using Jake's extension with all three perspectives loaded. Glitches happen every 15 to 20 minutes, it doesn't matter if I'm playing on a full registration or just two stops.
I can see the CPU monitor in HW's performance window spike way into the red. Then after I quit playing I can see it spike two or three more times without anything happening in HW.
The polyphony monitor never moves up more than a couple of green bars and the audio monitor only shows 1 green bar at the most. I have polyphony set at around 15,000. I'm using the 96kHz setting and tried switching to the medium performance level for modeling. Also tired switching back to 48kHz, changing buffer sizes and number of buffers, but the problem still happens.
The computer has an 13th Generation i5-13600K with base speed of 3.50 and 128 GB of ram. RME 803 Audio interface, latest drivers loaded.
I found an article titled "12 background apps to disable for better audio in WIn 11" that proceeded to list 20 things to disable, I disabled all of them, actually un-installed the ones that would let me do so. I have it set to High Performance Power management, nothing is allowed to sleep, all USB power management is disabled.
In HW audio trim is set to -10 and overall volume is at 60%. No Reverb Ir's are loaded.
When playing full out, huge chords and rapid scales, Windows task manager shows HW CPU usage at 8. 2%, so I don't think HW is straining the system, especially since it is just as likely to happen playing a duet on one stop as it is when playing on full organ.
I'm pretty sure this is a Win 11 problem. Task manager shows a bunch of background stuff open, but not using the CPU(I tried disabling a bunch of them that I thought looked unnecessary but I managed to freeze windows at some point).
I'm offline when this happens and no programs or browsers are open except for HW and the RME interface Total Mix.
Anyone have a clue what could be spiking the CPU usage or any other tips for improving audio?
Thanks

[mdyde]

Hello John,

There are lots of previous topics on this forum on troubleshooting audio glitches/performance on PCs. E.g. here's a recent one with some suggestions:

https://forum.hauptwerk.com/viewtopic.p ... 45#p155045

Please try working through these:

please first try working through the steps in that section ("Performance tuning | Other operating system and computer optimizations and diagnostics" which starts on page 308 [in the v7 user guide]). For example:

- Make sure that all available motherboard BIOS updates are applied.

- Make sure that all available Windows updates are applied.

- Make sure all available firmware and driver updates for hardware devices are applied, and especially so for audio/MIDI interfaces, the graphics card, and the motherboard. Check on their manufacturers' websites if needed.
...
- Make sure that Windows drive indexing is disabled for all drives.

- Make sure Windows Superfetch/sysmain is disabled.
...
- Try running LatencyMon ( https://resplendence.com/latencymon ) when Hauptwerk is running, and see if it reports any problems when the glitches occur.
...
- Make sure you aren't over-filling the PC's RAM. As a test, see whether the problem occurs with small sample sets, such as St. Anne's.

If that doesn't solve it, and if the problem is due to some other process occasionally hogging a lot of time at very high priority with its CPU affinity limited to one or more of the CPU cores that Hauptwerk is using for its audio engine (as in this thread: viewtopic.php?f=4&t=20531&p=154902#p154902 ), then upgrading to Hauptwerk v8 might help to mitigate it, since Hauptwerk v8 adjusts the loads assigned to individual CPU cores on a dynamic basis, so as to allow for cores with performances that differ relative to each other at each point in time.

John,
Just play pieces under 15 minutes
Steve

[mdyde]

That's an excellent suggestion!

Thanks Martin,
I should have mentioned that I had seen several other posts, including the one you quoted/ linked to. I have done all those things,
I've also disabled most of the services listed in this article
https://www.partitionwizard.com/news/wi ... sable.html
I've also followed the guide from Sweetwater for glitch-free audio in WIndows 11
and was still having the problem.
Per your suggestion, I upgraded to HW 8, loaded Velesovo Dry with only two stops, one manual and one pedal and had the problem occur in the first few minutes of playing.
With three of perspectives loaded from the Oakland AS organ, HW is saying I have 77GB of free RAM out of 128 so I don't Ram is being stressed.
Since I don't perform publicly on this instrument and I haven't published a Youtube video in a long time, it is not a huge problem, but an annoyance.
I'm going to call Dell and see if I can get Windows 10 to install on this machine.
I ran HW 6 with just the direct perspective of the Oakland AS loaded in a live performance situation for several months with Win 10 and a much less powerful computer without incident.
Hope I can get there again.
Thanks again,
John

Are you sure you've disabled all the Windows periodic services like drive indexing, sysmain, and checking for updates?15 - 20 minutes apart really sounds like one of those. It would be almost impossible to catch on Task Manager.

[mdyde]

Thanks, John (and also thanks very much for upgrading to v8).

I also have WIN11 and HW7 and experienced periodic audio glitches. In addition to doing all the Windows "tuning" recommended in the HW instruction manual and on the forum, I found that even though I thought I had disabled Windows defender anti-virus, it turns on automatically every time the machine reboots (and even sometimes during a long practice session). You have to turn off the anti-virus manually, every time. Also, if you aren't already doing so, turn off the wifi after you load your simplest.

Manually disable native Windows 11 anti-virus:
Go to Windows Security
Go to Virus & Threat Protection
Under Virus & Threat Protection, click Manage Settings
Switch "Real Time Protection" to OFF

Nvidia video drivers often produce high dpc latency. Its best to use Amd video cards for audio PC’s.
Search the net and you will read that lots off users have problems with high Dpc when using Nvidia cards in dedicated audio PC’S.
When you have a single monitor then you can try the generic windows video driver, but this driver does not support multiple monitors.

Jan

So after figuring out latency monitor and running it, two main culprits were found, tci/ip and acpi.sys interrupts. I turned off all ttci/ip in the wifi ans ethernet drivers and got it down to a bad interruption about once an hour. Searching the internet there are a lot if suggestions for acpi problems, with few of them appearing to work according to answers on the various forums.
One site suggests that acpi interrupts occur on cores 0 and 1 and that audio programs should be masked to use other cores with some suggested apps to help do this.
Does this sound plausible?
Apparently Dell computers are notorious for slow acpi hooks, whatever that means.
If anyone can point me toward a solution, it would be greatly appreciated. I have found a couple of suggestions I will try if I don't hear of anything else.

[mdyde]

Hello John,

Although it would be preferable to solve the underlying problem if possible (perhaps others have suggestions for that), if that isn't feasible, you could try the following, which might possibly help to work-around it:

- In Hauptwerk, tick the "General settings | General preferences | Advanced ...: Try to run Hauptwerk at real-time priority on Windows ..." setting. OK the screen and exit Hauptwerk. Whenever launching Hauptwerk subsequently, do it by right-clicking on the Hauptwerk icon on the Start Menu/desktop and selecting "Run as administrator". (Windows only allows applications to run at real-time priority if they're launched 'as administrator'.)

- If that still doesn't solve it, you could also try un-ticking the "General settings | General preferences | Advanced ...: Bind audio engine threads to CPU cores on Windows ..." setting. (It's best not to un-tick that setting unless really necessary, and if you do have to do it, always run at real-time/as-administrator.)

Thanks,
Martin, will keep looking for solutions on line, and also give your first suggestion a try.
John

[mdyde]

Thanks, John.

Nvidia video drivers often produce high dpc latency. Its best to use Amd video cards for audio PC’s.
Search the net and you will read that lots off users have problems with high Dpc when using Nvidia cards in dedicated audio PC’S.
When you have a single monitor then you can try the generic windows video driver, but this driver does not support multiple monitors.

Jan

Yes. Just to illustrate this thesis on my own hardware, I disconnected the eGPU enclosure that hosts an Nvidia RTX 2070 GPU (used for racing and flight simulators) and, without rebooting, connected a USB portable touchscreen monitor whose video signal is generated by the Intel iGPU. Look at latency differences over 3 minutes of intense multitasking and switching applications (there is no other optimization other than turning off the SysMain service):

Hello John:

I contributed to this thread and feel a key ingredient is; Click the HW Preferences check box to "try and run Hauptwerk in Real Time mode" and launch HW as Administrator.
https://forum.hauptwerk.com/viewtopic.php?f=4&t=20531&start=30#p154089

To verify, launch the Windows Task Manager, Click on the Details tab, find the Hauptwerk.exe program, Right Click on it then hover over "Set Priority". You should see that HW is running at the highest priority.

When Hauptwerk runs in Real Time mode all audio issues went away since the other Windows background tasks are suspended. This was only achievable by launching HW as Admin or clicking the "Run as Admin" box in the short cut properties. The caveat is you have to manually start HW from the desktop. To get HW to auto start when you boot the computer and run in Real Time mode will require some extra steps including using creating a simple batch file.

Danny B.