CPU-usage when starting Cantabile

Hey people,

since a few days I have a problem with the CPU.
I didn’t change anything on the system (as far as I can remember). The system doesn’t have internet access. So windows-updates are not possible.

What happens is that when booting the computer and starting Cantabile the CPU-usage is about 10% which seems to be okay. Now I have a very intense song with a few u-He Repro-5 instances loaded. I’m not able to play this song, because the CPU will go up to 120% and more. The solution is restarting the Cantabile audio engine. After that it will be at about 60% when playing the song which is normal.

I thought it might be related to Repro, but it’s not. Other songs also have a significant higher CPU-usage before restarting the audio engine.
It’s enough restarting the audio engine one time, after that this behaviour doesn’t occur anymore… whatever song I load. This occurs only after restarting the computer.

So, @brad is there anything we could do to investigate that?


Same here - some complex songs are unplayable before restarting the audio engine. I think there was a discussion about this some time ago, but not sure if anything came from it.

At the moment, my usual workflow at the beginning of rehearsal or gig is

  • boot up Cantabile
  • pre-load the setlist
  • quickly step through the set list (to make sure all relevant instruments get active)
  • re-start audio engine
  • start having fun!





seems to be familiar to the load balancing problem I mentioned months ago. Brad was so kind to implement the possibility to restart the audio engine as target in bindings. Since I implemented a binding: Song → On Load → Engine → Restart Engine (Quick) inside every song the problem never appeared again.

Regards, humphrey

Here the thread about load balancing


Yes. I’ve read your thread. But this binding I can not implement, because I have my reverbs and delays in the backgroundrack that allow me to switch between songs without cutting the tail of the reverbs.

@Torsten today I wanted to make a BIOS update which was not successful so the old BIOS was restored. I reconfigured the BIOS for my needs and you know what? The problem is gone?!?!?! I’ll check this more deeply and I hope I can identify the parameter that helped solving this.

Hmmm - that sounds intriguing! Do let me know what you find out - looking forward to any insight you gain.



Unfortunately I don’t have much to add to this. There’s nothing specific I can think of in Cantabile’s audio engine that would require a restart to kick it into gear and so I’ve always assumed this was some kind of driver/hardware peculiarity - and @FantomXR’s comment on the bios seems to confirm this.

One thing I’ve been contemplating adding to help give some insight into issues like this is a breakdown of the performance load - showing how much time is spent in each plugin, how much time in various parts of Cantabile’s processing etc… my main concern though is the overhead of capturing all that info.

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Personally, I would love something like this, provided you can keep the overhead manageable (and that we can disable this when necessary). There have been many times when I have noticed the CPU Load and/or Cantabile’s Load monitor maxing out, and I end up spending time disabling VSTs one at a time trying to isolate the culprit.

Mh… I don’t know if this can help the discussion:
I often use Cantabile and Audacity (both playing on the same audio driver).
I noticed that if, after booting the PC, i start Audacity first and then Cantabile, there is a problem on playing Cantabile VSTs (due to high CPU usage - infact it happens mostly on heavy VSTs). This seems not happening if i first start Cantabile and next Audacity…
I have a Focusrite 2i4 second edition, with its own audio driver.

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