I’m reaching out regarding critical and repeated crashes in Cubase 14.0.32 (on Windows 11, build 26100.1), which occur consistently while working on projects that use Kontakt 8.5.1 VST3.
Cubase crash reports point to access violations related to Qt components executed via Kontakt 8, usually referencing:
I’ve been in contact with Native Instruments support (ticket #4596139). They confirmed that Kontakt 8 uses Qt for GPU rendering and suggested reinstalling Kontakt and updating GPU drivers, which I already did — but the issue persists. The crashes do not occur in standalone mode, only inside Cubase.
Unfortunately, I don’t have a VST2 version of Kontakt installed, so I currently have no workaround and cannot work reliably.
Please find attached the latest Steinberg crash dump (.dmp) showing this consistent behavior.
Summary of steps already taken:
Reinstalled Kontakt 8
Updated GPU and all drivers from manufacturer site
Cleared Cubase preferences
Verified on multiple projects
Any help or insight would be greatly appreciated — especially in coordinating with NI or confirming whether this is a known VST3-related issue
Crash dump here -
Can you do a step-by-step so others can try to reproduce the issue?
It would be helpful if you could add your hardware details (GPU and driver version).
I have Windows 11 24H2 Build 26200.4652 here with Kontakt 8.5.0 currently.
hi,
Nvidia GeForce RTX 4060 latest driver (from 14th July), Win11 latest update (Windows 11 Version 24H2 for x64-based Systems (KB5062660) (26100.4770)) , Kontakt 8.5.1.
I’m allways have the latest updates on my pc and working with 128 ram.
Rme Ufxii latest update also. Cubase latest update.
I’m trying to figure out this issue for months.
thank you
off the top of my head the fact that in stand alone mode it’s OK could point to the multiprocessor support. Kontakt offers multiprocessor support, allowing it to utilize multiple CPU cores for improved performance, particularly in standalone mode. When used as a plugin within a Digital Audio Workstation , it’s often recommended to disable Kontakt’s multiprocessor support and let the DAW handle core allocation. This is because most modern DAWs efficiently manage multiprocessing, and enabling it in Kontakt can sometimes lead to conflicts or decreased performance.
Thanks for the suggestion. However, I always keep Kontakt’s multiprocessor support disabled when running it inside a DAW, as recommended.
The issue is not related to multiprocessing — it’s a memory access violation (c0000005) caused by Kontakt trying to execute code at an invalid address, as clearly shown in the crash logs (IP_ON_HEAP, ntdll.dll!RtlpTpTimerCallback).
This is a critical low-level issue, not a performance configuration conflict.
the component that is “complaining” is ntdll.dll, which is a Windows component, not Cubase.
When checking what that component is my search resulted in numerous results that explained how to repair ntdll.dll.
So maybe it is just a damaged Windows component that causing the problems, and worth trying to fix that one as a first step.
Have you tested your RAM? By that I mean using something like memtest86+ and leaving it to run several cycles (which will take quite a bit of time with 128GB).
Just to clarify — my Windows 11 system is completely stable and updated. I’m a professional composer, working daily with Cubase 14 for hours on end, with large orchestral templates, and Kontakt 8 is the only plugin that ever crashes.
There are zero issues when using Kontakt 8 in standalone mode, and no crashes when Kontakt is not loaded in the project.
This strongly suggests Kontakt is calling an invalid memory address, likely due to a Qt-related bug — not a hardware fault or damaged Windows component.
Still, I appreciate the insights and will continue testing. But this looks more like a Kontakt 8 VST3 bug than a Cubase or OS issue.
There’s very little else us fellow users can offer, but if you can provide a step-by-step to reproduce the crash (and that we could also provoke) I’m sure it would be very helpful for Steinberg developers. Have you logged the issue with Steinberg support?
Are you using the “Studio” driver?
Driver Name:
NVIDIA Studio Driver
Driver Version:
577.00
Release Date:
Tue Jul 22, 2025
The “Game Ready” driver is generally not as stable as the “Studio” driver.
The exception says that ntdll.dll is asked to execute code from an address from the heap (list) that is not flagged as executable code, using the RtlpTpTimerCallback function of ntdll.dll.
There probably will be an entry in the Windows System logs (Event Log), either in section System or Application.
Maybe its worth checking there for more detailed information, e.g. about the application that called that function in ntdll.dll.
As I am not a developer, I do not know what ntdll.dll is doing in detail, but as far as I found out it is a library from Microsoft that contains NT kernel functionality.
And yes, if the problem only appears if Kontact8 is loaded as a VST plugin, then the issue is pointing to Kontact8.
But my over 20 years as an IT supporter also taught me that, especially in Windows systems, one should never exclude a Windows system issue.
Please find here a guide how to fix ntdll.dll issues.
A damaged system file can be fixed by step 5 and 6.
Thanks for the suggestions and the detailed response.
Yes, I’ve already contacted both Native Instruments and Steinberg support and submitted crash dumps, screenshots, and all relevant info.
Regarding the GPU:
I’m using an NVIDIA GeForce RTX 4060 with the Studio Driver, version 577.00, released July 22, 2025 — so that should not be the issue.
About reproducing the crash:
It happens only when Kontakt 8.5.1 (VST3) is loaded in a project, and sometimes even just minutes after loading. There is no specific action that triggers it — just working normally in the project (editing, playing back, etc.).
The crash always shows:
vbnet
CopyEdit
c0000005 – INVALID_POINTER_EXECUTE
IP_ON_HEAP: Attempt to execute non-executable address
ntdll.dll!RtlpTpTimerCallback
Standalone Kontakt works flawlessly. Other plugins in the same project (including heavy orchestral libraries) don’t cause any problems.
This strongly suggests that the issue lies in Kontakt’s VST3 implementation, likely in Qt or GPU-related memory handling.
I’ll try to isolate a minimal project that reliably causes the crash and share it here if I can reproduce it consistently. Thanks again for the support.
@daniel_salomon as a workaround until this can be pinned down, you could try loading the Kontact instances in Audio gridder as that will open then outside the cubase process and possibly solve the issue.
Just install the AG plugin and HOst on the same machine, dissable the GUI ( local mode) and then load the AG plugin inside cubase as you would normally then load Kontact inside that. If you keep your contact pre sets you can just reload them in the AG version.
Not to say that this is your issue at all, but just sharing a similar K8 experience for others who might find this info helpful:
Kontakt 8 VST was causing all sorts of glitchy graphics and behavior, but not in stand-alone mode. It turns out that I had set G-Sync to “enable for windowed and full screen mode” which was causing the issue. I changed it to “enable for full screen mode” and the issue was completely resolved:
