Even when using a high-spec multi-core CPU (such as an AMD Ryzen or Intel Core processor), do you ever experience audio pops, clicks, or dropouts while playing back or recording projects in Cubase?
Furthermore, when you check the Task Manager, the overall CPU usage might only be around 10-20%, indicating plenty of processing headroom. Yet, inside Cubase, the “Real-Time Peak” meter inexplicably spikes and hits the limit, doesn’t it?
In this article, I will explain the causes of this phenomenon and provide a solution to prevent audio dropouts without compromising your CPU’s performance.
Why Do Audio Pops and Dropouts Occur Despite Having a High-Performance CPU?
One possible cause is the “conflict of real-time processing on a specific logical CPU processor,” which is difficult to detect just by looking at the overall average CPU usage.
Especially in certain environments, removing “CPU 0” from Cubase’s processing targets can resolve these audio pops and dropouts.
- How Windows Works
Devices such as graphics cards, USB controllers, and network adapters generate device interrupt routines like ISRs (Interrupt Service Routines) and DPCs (Deferred Procedure Calls). Windows assigns these processes to specific logical processors. - Cubase’s Multi-Processing
In some environments, the aforementioned Windows processes and Cubase’s real-time audio processing can conflict with each other on the same logical processor.
As a result, the moment “graphics or OS interrupt processes” kick in on CPU 0, Cubase’s real-time audio processing is momentarily put on hold.
If Cubase’s real-time audio processing cannot secure enough time due to these interrupt processes, it fails to meet the ASIO buffer processing deadline, resulting in audio pops and dropouts.
Solution: Exclude “CPU 0” from Cubase’s Processing
The solution is simple. You just need to exclude “CPU 0” from Cubase’s processing and configure it to run on CPU 1 and the subsequent cores.
- By removing “CPU 0” from Cubase’s CPU affinity, you reduce the likelihood of Cubase threads executing on CPU 0, thereby mitigating conflicts with OS and driver-related processes.
- When CPU 0 is excluded from Cubase’s affinity, Cubase’s threads will execute on the logical processors from “CPU 1” onwards.
By limiting the logical processors used by Cubase as described above, you can reduce the possibility of Cubase’s processing conflicting with OS and driver-related processes on a specific CPU.
Unlike the traditional workaround of “disabling the multi-processing function” in Cubase’s audio settings, this measure retains and utilizes the distributed processing power of the numerous cores from CPU 1 onwards. Therefore, even in large projects, the limitation on CPU resources is kept relatively small.
Procedure for “Setting Core Assignments” Using Process Lasso
While it is possible to change the CPU affinity (assigned cores) using the standard Windows Task Manager, the settings will be reset when you restart your PC or Cubase.
Therefore, we will use a background process management tool called “Process Lasso” to make the settings persistent.
Step 1: Installing Process Lasso
Download and install Process Lasso (the free version is fine) from Bitsum’s official website below, and leave it running in the background.
Step 2: Setting Affinity for the Cubase Process
- Launch Cubase.
- Open Process Lasso, and from the process timeline list, right-click on Cubase.exe.
- Select “CPU Affinity” > “Always” > “Select CPU affinity”.
- When the list of cores appears, uncheck “CPU 0” and click OK.
Step 3: Comparing the Changes Caused by the Settings
Compare the state with CPU 0 included versus excluded, using the exact same project, sample rate, ASIO buffer size, and plugin configuration.
If the real-time peak spikes and dropouts noticeably decrease after excluding CPU 0, it is highly likely that changing the CPU Affinity was effective in your environment.
*If Affinity Settings Revert Due to Cubase’s Behavior
Depending on the environment, the settings might not be maintained due to how Cubase behaves.
In that case, you can also try configuring it via “CPU Sets” separately from CPU Affinity, so please consider that option as well.
Supplementary & Additional Settings: GPU and Power Saving Optimization
Power Management for NVIDIA / AMD GPUs
If changes in the GPU driver or power state are suspected as one of the causes, it is worth trying this to isolate the problem.
In the NVIDIA Control Panel, under “Manage 3D settings,” add Cubase.exe and set the Power management mode to “Prefer maximum performance,” then observe the changes.
Disabling Core Parking
By disabling Core Parking using tools like “ParkControl” included with Process Lasso, the behavior of CPU cores waking up from sleep states changes. In certain environments, this can stabilize real-time processing at low buffer sizes.
Also Check: Verifying “DPC Latency” with LatencyMon
Another method I would like to propose for investigating the causes of audio pops and dropouts in Cubase is “checking with LatencyMon.”
In the article below, I explain in detail how to check the status of “DPC Latency” using LatencyMon to identify problems. If the issue is not resolved by this current article, please refer to that one as well.
Summary
One possible cause of audio pops and dropouts in Cubase is the “conflict of real-time processing on a specific logical processor,” which is difficult to grasp from the overall average CPU usage.
In Windows, processes such as ISRs/DPCs occur in relation to devices like graphics cards, USBs, and networks. Because these processes are executed on specific logical processors, they can conflict with Cubase’s real-time audio processing depending on the timing.
In Cubase’s real-time processing, each audio buffer must be processed within a predetermined time frame. Therefore, even if the overall CPU usage is low, audio pops and dropouts may occur if sufficient processing time cannot be secured on a specific logical processor.
Thus, in some environments, by excluding CPU 0 from Cubase’s CPU Affinity, the likelihood of Cubase’s threads and OS/driver-related processes conflicting on the same logical processor is reduced, which can potentially stabilize real-time performance.
If you are looking to run Cubase at low buffer sizes or seeking real-time stability for large projects, please use the information provided in this article as a reference.
