Logic Pro latency: buffer size table and how to get the delay down

Platform and version

Match the symptom to the first thing to check

Diagnosis order

1. Read the number Logic gives you. Open Logic Pro > Settings > Audio > Devices. Under the I/O Buffer Size menu Logic shows the resulting latency, including the roundtrip value from input to output. Apple's article confirms this readout is where to look first.
2. Test in an empty project. Press Shift-Command-N, add a software instrument, play it. If the delay is acceptable here, the extra delay in your project comes from plug-ins.
3. Check the live track's plug-ins. Dynamics plug-ins with look-ahead, linear-phase EQs and some mastering tools add their own delay that Logic compensates on playback but cannot hide while you play.
4. Check the Stereo Out. A limiter with look-ahead on the master adds latency to everything you monitor.
5. Check your output device. Bluetooth adds latency Logic cannot remove.
6. Then apply the fixes below.

Fixes

Choose the right I/O Buffer Size

Choose Logic Pro > Settings > Audio > Devices (Preferences on macOS 12 or earlier), pick a value from I/O Buffer Size and click Apply. The one-way delay added by the buffer is the sample count divided by the sample rate. The table gives that figure; the real figure you hear is the roundtrip, which adds the input buffer, the interface's analog-to-digital and digital-to-analog conversion, and any driver safety buffer, so it is higher and varies by interface. Logic displays its estimate under the menu.

Apple's guidance in its latency article: start at the lowest setting when recording and move up one step each time you see an overload alert. Expected result: at 128 samples or lower most players stop noticing the delay.

Turn on Low Latency Mode

Choose Record > Low Latency Mode. According to Apple, it routes audio around plug-ins that add latency, such as dynamics plug-ins with look-ahead, so that the delay along the current track's signal path stays under a limit. Set that limit in Logic Pro > Settings > Audio > General: turn on Low Latency Mode there and drag the Limit slider in the Plug-in Latency section, in milliseconds. Bypassed plug-ins show as orange in the channel strip and come back when you turn the mode off. Expected result: the live track feels as fast as an empty project. Turn it off before you mix, or bounce, so every plug-in is active.

Software Monitoring vs direct monitoring

For audio recording you have two ways to hear yourself. Software Monitoring (Logic Pro > Settings > Audio > General) sends the input through Logic and its plug-ins, which costs the full roundtrip latency but lets you hear effects while you record. Direct monitoring is a mixer in the interface that sends the input straight to your headphones with no buffer; turn Software Monitoring off and use the interface's mix knob or control app instead. Use one or the other: both at once produces a doubled, phasey sound. Apple's overload article notes that with Software Monitoring off you can leave the buffer at 256 samples for audio recording with no felt delay, because Logic is no longer in the monitoring path. Software instruments must go through Logic, so direct monitoring does not apply to them.

Understand plug-in delay compensation

Choose Logic Pro > Settings > Audio > General and look at Plug-in Latency Compensation. Set to All, Logic delays every other track to line up with the slowest plug-in so playback stays in time, which is what you want for mixing. The cost is that every track, including the one you are recording, is monitored through that delay. Set to Audio and Software Instrument Tracks, aux and output plug-ins are not compensated, which keeps the live path shorter at the expense of timing on busses. For tracking, Low Latency Mode is the better tool because it leaves the setting alone and simply bypasses the offenders.

Processing Threads and the buffer

A smaller buffer gives the CPU less time per cycle, so a project that runs at 512 may overload at 64. Logic Pro > Settings > Audio has a Processing Threads menu that Apple recommends leaving on Automatic, and a Multithreading menu in Devices whose Playback & Live Tracks option spreads live input across cores. If low buffers overload, set Multithreading to Playback & Live Tracks, freeze finished tracks and follow the system overload page. Expected result: a lower usable buffer without alerts.

Avoid Bluetooth while playing

Apple's latency article is direct: wireless headphones and speakers add latency, so use them for listening and mixing only. Switch the Output Device to a wired interface or the headphone jack when you record or play instruments.

Fix the Recording Delay

If recorded regions land consistently early or late against the click, the interface is reporting its latency incorrectly. In Logic Pro > Settings > Audio > Devices, adjust Recording Delay in samples, negative to pull recordings earlier. Measure it by recording the click through a loop-back cable and reading the offset in the Sample Editor. This does not change what you hear; it changes where the audio is placed.

Verify the fix

1. Open Logic Pro > Settings > Audio > Devices and read the resulting latency under the I/O Buffer Size menu. Note the roundtrip value.
2. Record-enable a software instrument track and play a few notes. If you can play in time without thinking about it, the buffer is low enough.
3. Open your heaviest project, turn on Record > Low Latency Mode, and play the same test on its live track. Orange plug-ins show what was bypassed.
4. Record 8 bars of a click through an audio track with Software Monitoring on, then with it off and direct monitoring on. Choose the one that feels right and leave the other setting off.
5. Before bouncing, turn Low Latency Mode off and confirm no plug-ins are orange.