Logic Pro system overload: how to fix the error (-10011)

Platform and version

Match the symptom to the first thing to check

The alert text is the same in every case, so what you were doing when it appeared is the real clue. The error code -10011 and the wording below are what users report seeing in the alert; Apple's support article refers to it only as the system overload alert.

Diagnosis order: do these before you change anything else

Apple's system overload article is a list of settings, not a procedure. This is the order that finds the cause fastest, and it leaves a reinstall off the list because a reinstall changes none of the settings involved.

1. Quit every other app except your audio interface's control software. Browsers with many tabs and video calls are the usual CPU thieves.
2. Turn on the meters. Choose Logic Pro > Settings > Advanced and select Enable Complete Features. In the control bar, click the Display Mode disclosure triangle and choose Custom so the CPU and HD meters appear.
3. Open the Performance Meter. Double-click the CPU or HD meter. It shows one bar per processing thread plus a Drive I/O bar. Play the project up to the point where the alert appears and watch which bar hits the top.
4. Decide: CPU-bound or disk-bound. If a Processing Threads bar peaks, the fixes are buffer size, multithreading, freezing and plug-in load. If Drive I/O peaks, the fixes are disk location, format and Sampler Virtual Memory.
5. Note which track is selected when it happens. A selected software instrument track or track stack header is kept live for input, which costs CPU on one thread.
6. Check the sample rate in File > Project Settings > Audio. A 96 kHz project doubles CPU and disk load compared with 48 kHz.
7. Only then work through the fixes below in order.

Fixes, in the order Apple recommends

Raise the I/O Buffer Size

Choose Logic Pro > Settings > Audio > Devices (Preferences on macOS 12 or earlier). From the I/O Buffer Size pop-up menu choose the next larger value and click Apply. Repeat until the alert stops. Apple's guidance is to use a small buffer while recording and a large one while mixing, because every step up adds monitoring latency. Expected result: the alert stops during mixing at 512 or 1024 samples on almost any project. If you are recording audio only and software instruments are not involved, deselect Software Monitoring in Logic Pro > Settings > Audio > General and leave the buffer at 256; you then monitor through your interface instead. Latency numbers for each buffer size are on the latency page.

Set Process Buffer Range to Large

In the same Devices pane, set Process Buffer Range to Large and click Apply. This is the buffer Logic uses for tracks that are not live, so it costs no monitoring latency. Expected result: fewer overloads on playback-only tracks with no change in feel when you play.

Set Multithreading

Still in Devices, the Multithreading menu has two options. Playback Tracks runs all live input DSP on a single thread. Playback & Live Tracks spreads it across cores when a track stack with several software instruments is selected or several audio tracks are recording. According to Apple's Multithreading article, the second option adds a little total load, so try both; if you never record more than one track at a time, Playback Tracks can be the better choice. Expected result: overloads that only happen with a stack or multiple armed tracks go away.

Leave Processing Threads on Automatic unless you must

Logic Pro > Settings > Audio has a Processing Threads pop-up menu. Apple describes Automatic as the recommended setting and warns that the highest thread count is not always best. Change it only when another heavy app, such as a video editor, must run beside Logic, then click Apply and compare the Performance Meter.

Turn off Sample Accurate Automation

In Logic Pro > Settings > Audio > General, set Sample Accurate Automation to Off if you do not need it, or choose the option that covers only the parameters you automate. Expected result: a small but measurable drop on every thread in a heavily automated mix.

Select an empty track during playback

Click an empty audio track before you press Play. A selected software instrument track or track stack header stays live for input, which forces its whole plug-in chain onto one thread. Apple suggests using the Performance Meter to confirm: if the spike disappears when you change the selection, that track is the cause. Expected result: an immediate fix for the "same spot every time" overload.

Freeze the heaviest tracks

Control-click a track header, choose Configure Track Header, enable the Freeze button, then click the snowflake on the tracks with the most plug-ins and press Play once to render them. Apple adds one caveat: if your overloads coincide with Drive I/O peaks rather than CPU peaks, do not freeze software instrument tracks, because freezing turns a CPU load into a disk load. Expected result: frozen tracks drop to almost zero CPU.

Use send effects for reverbs and delays

Instead of one reverb per track, add a single reverb on an Aux and feed tracks to it with sends. If a track needs its own reverb, Apple's article points to SilverVerb or PlatinumVerb as less CPU-intensive choices. Expected result: a large reduction in thread load in reverb-heavy mixes.

Lower voice counts and lower the sample rate

Open each software instrument and set its voice count to the lowest number you need; polyphony costs CPU whether or not you play that many notes. If the project does not need it, a lower sample rate in File > Project Settings > Audio cuts both CPU and disk load, at the price of audio quality for the final output.

Fix disk-bound overloads

If the Drive I/O bar is the one peaking, the disk is the limit. Apple's recommendations: save large projects to an external SSD rather than the startup disk; keep Sampler libraries on a dedicated drive; and format any drive used with Logic Pro as APFS or Mac OS Extended (Journaled). Then open Logic Pro > Settings > Audio > Sampler > Virtual Memory: enable Active if overloads coincide with Processing Threads peaks, disable it if they coincide with Drive I/O peaks; set Buffer Range to Medium or Large; set Host Disk Activity to Average or Extensive when the project has many audio tracks. These settings are global for every Sampler instance in every project. Expected result: the Drive I/O bar stays below the top during playback.

Add RAM only if the meters say so

Apple lists more RAM for projects with many plug-ins or Sampler instances. On Apple silicon Macs memory is not upgradeable, so this means choosing a higher-memory configuration at purchase. It is the last resort, not the first, because every fix above is free.

Verify the fix

Keep the Performance Meter open and run this test after each change rather than after all of them, so you know which one worked.

1. Select an empty audio track, press Return to go to the start, and play the whole project without touching anything.
2. Watch for any Processing Threads bar or the Drive I/O bar reaching the top. A brief touch is fine; a sustained full bar means the alert is still possible on a slower day.
3. Arm the track you record on most, play or sing through it with Software Monitoring on, and confirm the alert does not return at your recording buffer size.
4. Save the project. Buffer size, Process Buffer Range and Multithreading are global settings and stay set for every project; Sample Accurate Automation and the sample rate are per project.

If a project still overloads after every step, the cause is the sum of its plug-ins rather than any setting. Bounce the finished tracks in place and remove their plug-in chains, or open a new project and import only the tracks you still need via File > Import > Logic Projects.