Cubase 13 high CPU usage with no projects loaded (Hub)

theMidiTamer · June 18, 2024, 9:25am

Hi there,

I was wondering why Cubase 13 consumes significant CPU power when no projects are loaded and only the Hub is open. (in the screenshot no other apps are opened, just Cubase)

It should be noted that this issue occurs after a project has been closed. This does not occur for example when starting Cubase 13.

Not sure if this makes sense, but this always makes me quit Cubase every time I need to open a different project, as I’m concerned about not having the same resources available for the new project.

Any ideas? (Windows 10, Cubase 13.0.40)

JuergenP · June 18, 2024, 9:35am

Even if you do not have applications open, there are many background processes in Windows that are still active.

Your screenshot just shows the overall CPU, have a look at the processes that are running in the background and see what they consume in CPU time. I’m not really familiar with the standard Windows task manager (I think it is just ugly), I use ProcessExplorer, which is available from Microsoft and gives much more information.

Prozess-Explorer - Sysinternals | Microsoft Learn

theMidiTamer · June 18, 2024, 10:04am

Thanks for your reply.

That screenshot was not very clear, my bad. I took two new screenshots for comparison, taken after a few minutes of inactivity to avoid any spikes or unrelevant events.

Cubase freshly started, only Hub opened, no other apps running on Windows

Cubase after a project has been closed, only Hub opened, no other apps running on Windows

I can clearly hear fans spinning in the latter case, that was the reason I noticed this issue at first.

JuergenP · June 18, 2024, 10:09am

Sorry, but as I said there are definitely other processes running in the background and your screenshots still show just the general overview, not the details of what is active in the back.

So can you please click on the details tab (dettagli) and have a look at all the running processes and their specific CPU consumption.

st10ss · June 18, 2024, 10:34am

It takes time for Cubase and for Windows to rearrange memory and write cached data to the disc. And Windows is still doing things in the background.

It is not possible to run Windows without any app, since many system tools are already apps.

vinark · June 18, 2024, 10:57am

Maybe you missed that core 5 and 13 are running at 100%, it should absolutely not do that.

JuergenP · June 18, 2024, 11:01am

That shows that there is still background activity, but the screenshot does not tell you what process or service that is. The overall CPU consumption is still around 14% and lots of CPU resources available.

A complete task list is needed to tell what is going on, as @st10ss said, there is probably some cleanup of cache data ongoing. But that is a guess, without details you don’t know.

csurieux · June 18, 2024, 11:27am

Beware of any GDrive or OneDrive or similar.

Googly_Smythe · June 18, 2024, 12:01pm

I think the Processes tab (the first one) would be more informative.

I just tried it, opened a full project (around 37% CPU, RAM at 50% of 64 gbs), used the File->Close menu item to close it, the hub appeared, CPU at 3%, RAM at 24%).
I have Shadow of the Tomb Raider and this browser open as well.

theMidiTamer · June 18, 2024, 1:03pm

Sorry, but as I said there are definitely other processes running in the background and your screenshots still show just the general overview, not the details of what is active in the back.

So can you please click on the details tab (dettagli) and have a look at all the running processes and their specific CPU consumption.

I’m sorry, but that doesn’t make sense. The other processes running in the background are always running, in both cases. They use the same amount of resources before and after. And they’re not related to Cubase.

And to confirm this, since you asked, here’s more details. As you can see, Cubase process alone is making the difference.

Screenshot taken as stated above, waiting for a couple of minutes doing absolutely nothing, to avoid any interference and allow Cubase to shut down the project (in the second case).

JuergenP · June 18, 2024, 1:26pm

That is not true, there is always a possibility that an application starts another process in the background, that was not there before and this process survives.

One example is the Mediabay Server. This does not exist until you launch Cubase for the first time.

And it stays after Cubase is shutdown, so it is not always the same.

Your screenshot shows exactly what @st10ss assumed that happens. Cubase is not down at the moment and still working on something. It is hard to tell what the Cubase Pro Hub is doing here, but that is the process consuming the CPU resources.

One possible issue here could be it is waiting on the cleanup of some interface driver or VST instrument that was loaded in your project.

theMidiTamer · June 18, 2024, 2:01pm

I hadn’t considered that, my focus was on reading CPU values rather than memory usage. It’s really beyond my knowledge, so I trust what you say.

Still hope a staff member can shed a light on this matter and give some advice. I’ll keep closing and restarting Cubase everytime I finish working on a project for now.

rickpaul · June 18, 2024, 4:14pm

I initially just saw the original post in the thread, so decided to do a quick experiment to see if I saw similar behavior. I am running Cubase Pro 13.0.41 on Windows 10 (fully updated), and a much(!) older system than the one in the post.

I started by loading Cubase and playing a project I just finished, waiting for on the order of a minute to let the CPU graphs in Task Manager stabilize:

Next I stopped playback, again waited on the order of a minute for the graphs to get current:

Finally, I closed the project, just returning to the Hub, again waiting for a minute to let the graphs stabilize (since they’d initially show data from having the project open):

As can be seen, overall CPU level is significantly different between playing back (20%), sitting idle in the project (8%), and just the Hub (3%).

I hadn’t read through the rest of the thread by that point, so hadn’t yet seen the process details that showed the high CPU and memory use in the Hub on the original poster’s system. I don’t know what sort of things the Hub does, but my experiment would at least to suggest there is something system-dependent going on to account for the significant difference between what the original poster is seeing and what I am seeing.

The main reason I’m replying, though, relates to the quitting Cubase before opening another project, with the assumption that performance in the next project would be bad due to whatever is making the Hub’s consumption so high. I wonder if this has actually been observed? In particular, it seems conceivable to me that the Hub might be doing some sort of cleanup, taking advantage of there not being a project active, but, if another project were opened and active, the project would take priority over whatever might have been going on in the Hub. (The analogy would be that Windows only runs certain tasks when the system is sufficiently idle. In the case of Cubase, when a project is open, the audio engine is running, whether playback is going or not. I’m not sure if the Cubase power plan only kicks in when a project is open or if it is also activated when the Hub is open, but I do know that, when it is active, Cubase is always using high power – electrical, not necessarily CPU.)

Timo00 · May 15, 2025, 4:32pm

Wanted to chime in here because I am seeing this issue on Cubase 14 running on Windows 11 as well.

As you can see here, only the hub is running (there are no other Cubase child processes in task manager):

What could the hub possibly doing that eats up almost 10% of a high-end system?

FWIW, this is after closing a project and going back to the hub.