What's wrong with CPU usage on Cubase 8 ?

Anyone else noticed that the performance in C8 is really CPU heavy ?
I hoped for a fix on 8.0.5 but my projects even with few Plugins/VSTi are still overloading the CPU causing ASIO peaks and forcing me to put the buffer at maximum size to be able to work.

Any thoughts?

Any thoughts?

Aloha h,

Just the opposite here. All my projects: (even my heaviest project designed just to tax the system to the max)
shows slightly less cpu juice usage when using C8P compared to using C6.5/7/7.5

That being said:
to a certain extent tho’, you are probably right.

Reason being,
there are several posts on this board that agree with you on this topic.

Perhaps someone will start a poll on this issue to see where we all stand on this.

looove yer avatar. So kool the way some of the indicators go right up to the line, but never clip. Nice!

Good Luck!

Are you running MIDI Time Code? If so, you are likely to get CPU spikes. I just picked up Cubase 8 a few days ago and did the update. I’m running C8 on a Windows 7 64-bit system. I use the Tascam DM-3200 board as a control surface and (sometimes) as my audio interface. Had erratic CPU usage in both C8 64-bit and 32-bit mode (less so with the 32-bit version). After doing some research, it appears as if as of Cubase 7.5.03, this issue arose so many users rolled back to 7.5.02. I’d figure that 8 would have fixed it. Doesn’t appear so. As I type this, I’ve been listening to a project with a fair amount of processing, low buffer settings, etc., and very smooth playback. However, once I engage MTC in Cubase, the CPU spike problem returns.

However, if you delete your preferences in safe mode and then re-start normally and then re-built your preferences, this apparently corrects the problem. Testing it now.

See e.g.:


For me, it’s a steady build to unusability. Projects start ok, but CPU usage seems to… Accumulate! Without adding anything new, CPU starts spiking more and more, eventually leading to dropouts.

@ enjneer
That issue sounds like a memory leak. Using any new plugins?

same. what are you using? im use slate vst2… uad… soundtoys native instruments compressors alot.

It totally does sound like a memory-leak. My thoughts exactly, except it only happens in C8.
So it’s not a leak–unless C8 causes it…

Start your task manager, open the offending Cubase file, then monitor CPU usage of Cubase while the project is running. If it slowly creaps higher, then yes…its a leak.

Fwiw, I did this 2 days ago and yes…there is a memory leak in my system. My resolution? Just bought new motherboard, CPU and ram. Going to reload a fresh is and Cubase and see if that fixes my problems.

If you scan the forum, you can find my post on the subject entitled “at my wits end about vst performance…” Something like that. I am going to update it after the new build


my system is actually running great. C8 runs excellent here.
I am not using MTC though.
Of course, Cubase does not run very well on super low latency on the mac.
This has been like that for a long time, an ASIO Guard doesn’t change that really.
I can live with 512 Buffersize.
Right now i am working in a big project using lot of VSTi*s,
Vienna Instruments, Kontakt 5 and many others.
I am amazed how well the performance on my system is.

Performace problems are mostly related to 3rd party soft and hardware in my experience.
Therefore its always good to keep your system as slim as possible, use only what you really need.
Get rid of unused plugins or hardware!

just posting this to give another opinion.


I wonder if there’s any connection to this issue http://www.steinberg.net/forums/viewtopic.php?f=230&t=71314&view=unread#p426980 particularly in reference to RAM incorrectly unloading?

This is all great, general advice (good motherboard/RAM/clean system/task manager/memory leaks, etc.) But does nothing to explain why these issues pop up only in Cubase 8.

It’s all OT, too. OP asked for comments from others that are experiencing the issue.

If my system was corrupt, or memory leaking, it would affect everything–including C7.5 (which runs perfectly). There is something wrong with C8. Period.

The fix might end up being simple, it might get patched, it might be something that’s common to all the systems running C8. Who knows. I’m open to the solution. But the problem is not my rig or how I run it.

So the Slate VBC the Vari Mu, is memory leaking. the latest update is causing huge problems with cubase…

I figured it out by dropping it in 1 by 1.

The previous update Version stops cubase cpu spikes. I hope this helps some people.
Im over the moon finally getting some where with cubase.

I have also read the slate VMR is also memory leaking.

IM slowly getting cubase to almost stable but still a heap of bugs… slate is a major problem…

also the new ilok update fixed some issues also.

do not go near vst3 with slate.


I was having the same problem. However when I installed C8 on my new Macbook (running Yosemite), works perfectly. No issues whatsoever – so far.

I’m having the same problem, Cubase 8 is just chuck full of issues. Also the project song key is not getting saved with the song. I don’t know if anyone else is having that same problem.

It’s weird - I’m having exactly the opposite issue! (not that it’s an issue the other way round) since installing Pro 8 my CPU usage has dropped through the floor to almost idle. I had Cubase 7.5 Artist - obviously by upgrading to Pro 8 I also upgraded my 7.5 artist to the full version by definition. After fixing all the VST plug in paths broken by the install (Grrrr!) not only does CB 8 hardly use CPU - CB7.5 projects which were CPU peaking are now hardly using CPU. Tracks with a dozen instances of guitar rig and several Kontact 5s use just over 25% cpu according to Cubase. In windows resource monitor CPU load seems to be spread more evenly across the 8 engines - I wonder if I’ve accidentally fixed a problem I didn’t know I had? So far CPU use in Cubase 8 has been impressively low and project for project - slightly lower than the (now fixed) Cubase 7.5 and I’m terribly lazy when it comes to group and send tracks - I use far too many individual plugins.

That’s interesting.

In this thread there’s a couple of macbook pro users not having issues and you both are using Yosemite. I still haven’t upgraded past 10.8.6 on my MBPro Ret (mid 2012) since I haven’t heard of anyone’s success and Steinberg’s official warning against it (untested), but maybe I missed a new press release saying it’s supported.

At this point I think I have tried everything and my cpu still spikes with almost nothing going on. It spikes with a FF800, UR44 and an Apollo Twin all leading the way, not to mention internal core audio also spiking with no interfaces attached. All the talk of memory leaks, even if it’s only related to C8, has me scratching my head because I wouldn’t know where to start in trouble shooting. 90% of my template is Kontakt 5 and it spikes if ONLY Kontakt is loaded.

I’ll wait to hopefully get feedback from you guys running Yosemite before I try that route, but it’s an option I haven’t considered thus far…


I’m having the same problems as the thread opener.
Sometimes it also keeps piling up the cpu use, without me doing anything.
I also had nothing like this with Cubase 7.5
I just had to re save a project with just very few plugs cause it was unplayable anymore with latency of 1-2 seconds.
My task manager doesn’t show anything, Cubase taking 7% and nothing else really.
But Cubase itself shows almost 50 % average and spikes going up to 100% , in the end the project crashed Cubase right away after start and the meter showing HD Activity stayed up in red, again nothing in my task manager.
I’m working on Win 7 64 bit, everything 64 bit, no bridged plugs.
Intel i7 quad core with 16 GB Ram