MacBook Pro, mouse is lagging.

MacBook Pro M4 — Intermittent Trackpad Problems

Problem description

On your MacBook Pro M4 running macOS Tahoe 26.5.2 (25F84), the built-in trackpad intermittently stops registering finger movement for up to 20 seconds, even while you're actively moving your finger across its surface.

This isn't normal behaviour. The steps below focus on the built-in trackpad and aim to determine whether the cause may be macOS, software interference, system performance, or a hardware fault—without assuming the cause in advance.

1. Check basic trackpad operation

• Use one finger to move the pointer.
• Ensure the trackpad surface is clean and dry.
• Connect your Mac to power and check whether operation improves.
• If needed, connect an external keyboard to check for a hidden low-battery alert.

Apple's guide: Trackpad pointer troubleshooting

2. Test while the trackpad is unresponsive

During an interruption:

• Press Command + Space to open Spotlight.
• Press Command + Tab to switch apps.
• Test an external mouse, if available.
• Check whether physical clicking still works.

Interpret the results:

• External mouse works: The issue may be specific to the built-in trackpad or its input handling. This does not prove a hardware fault.
• Both pointer devices fail, but the keyboard works: A broader pointer-input or system issue becomes more likely.
• The keyboard and other apps also become sluggish: Investigate broader system performance or software problems.

These are clues, not definitive diagnoses. You do not need to buy a mouse; borrow one if possible.

3. Try simple fixes

1. Restart: Save your work and restart the Mac. Check whether the problem returns.
2. Disconnect accessories: Unplug unnecessary hubs, docks, and USB devices. Test the trackpad, then reconnect accessories one at a time.
3. Check for updates: Go to Apple menu >> System Settings >>General >> Software Update and install applicable updates.

There is currently no confirmed evidence that macOS Tahoe 26.5.2 has a specific bug causing this symptom.

4. Check system performance if other things are slow

Activity Monitor is most useful if apps or macOS also become sluggish. It is less informative when only the built-in trackpad stops responding.

Open Applications >> Utilities >> Activity Monitor. Check the CPU and Memory tabs for unusually high resource usage and note whether it coincides with the interruptions.

Apple guide: Activity Monitor User Guide

5. Test in Safe Mode

Safe Mode helps assess whether software loaded during normal startup contributes to the problem.

1. Shut down the Mac.
2. Hold the power button until startup options appear.
3. Select your startup disk.
4. Hold Shift and choose Continue in Safe Mode.

Use the trackpad long enough to see whether the problem returns.

If the issue disappears, software interference becomes more plausible. If it persists, the cause could still be software or hardware.

Apple instructions: Start up your Mac in safe mode

6. Run Apple Diagnostics

1. Shut down the Mac and disconnect unnecessary accessories.
2. Hold the power button until startup options appear.
3. Release it, then hold Command + D.
4. Follow the onscreen instructions.
5. In macOS Tahoe 26 or later, select a dedicated trackpad diagnostic if offered.
6. Record any reference codes.

A clean result does not rule out every intermittent fault. If a code appears, share it with Apple Support or an Apple Authorized Service Provider.

Apple instructions: Use Apple Diagnostics to test your Mac

7. When to contact Apple

Seek support if the issue persists after restarting and testing in Safe Mode, or if Diagnostics reports a problem.

Describe it precisely: the built-in trackpad intermittently fails to register finger movement for up to 20 seconds, then resumes working. Mention whether clicking works, whether an external mouse remains responsive, and any diagnostic codes.

Runaway processes and low free storage space are common reasons for Macs to run slow / beachball. 

It is possible there are processes running in the background that are using significant resources. Check Activity Monitor, CPU tab (sort by % CPU) and Memory tab (sort by Memory) to see what's running hard. Make sure that View menu > All Processes is selected, so you are seeing everything.

Activity Monitor User Guide for Mac - Apple Support

Confirm that you have sufficient free space on your internal storage. The absolute minimum is ~30-40 GB free space, and as a rule of thumb you should aim to have 15-20% of your total internal storage as free space. You can check the amount of free space you have on your Mac in a variety of ways:

Select your internal drive then click File menu > Get Info, check Available space

• Go to System Settings > General > Storage, check the graphical display at the top of the settings pane
• In Disk Utility (in Applications > Utilities), by selecting the main container disk below the drive itself (you may need to select View menu > Show all devices to see it)
• In the System Report – hold the Option key and click the Apple menu > System Information (the top menu item), look for the name of your internal drive (Macintosh HD, unless you have renamed it as I did)

Note that on versions of macOS prior to Golden Gate, the ‘available’ space reported with the first two methods above was greater than the ‘free’ space reported by the second two methods. Apple corrected that confusion with Golden Gate, and as shown in the above screenshot, the available/free space is consistent across the different methods. For more details, see this User Tip.

Some steps to take to safely free up space:

Free up storage space on Mac - Apple Support

Optimize storage space on your Mac - Apple Support

How to free up ‘System Data’ and other st… - Apple Community

If nothing in the above reveals an obvious culprit, then appropriate troubleshooting steps are Safe Mode and creating a new user account to test. 

See if the problem is present when you boot in safe mode. That process performs some system cleanup and clears caches, and also disables 3rd party extensions that may cause problems.

Start up your Mac in safe mode - Apple Support

If that does not correct the issue, test in a new user account. A newly-created user account will have all settings at default, and if the issue does not occur in that new account then it provides guidance on what may need to be changed to correct the issue.

Add a user or group on Mac - Apple Support

Once the testing is complete, the new account can easily be deleted.

Delete a user or group on Mac – Apple Support

If you have 3rd party ‘protection’ software installed, that may be the problem. That includes:

• Cleaners (software claiming to automatically free up space)
• Optimizers (software claiming to make your Mac run faster)
• Antivirus software
• VPN software (unless provided by a school/employer to enable access to internal resources from a remote location)

Such 3rd party system ‘helpers’, ‘cleaners’ and ‘protectors’ do more harm than good. In fact, such products are completely unnecessary for macOS and the only ‘good’ (if you want to call it that) they do is to put money in the developers’ pockets. Cleaners and protectors cause compatibility issues, often after macOS updates. Commercial VPNs claim to hide your browsing activity from websites, and while that may be true those VPN providers just sell your browsing data to others. For the user, all of these types of software offer only harm…and if that is limited to harm to your bank account, then count yourself lucky. If you have installed such software, follow the developer’s instructions to completely uninstall it (note that some developers fail to provide instructions and their software installs can be pervasive, meaning the only way to truly remove it is to erase your Mac, reinstall macOS then restore your user files from a backup).

It might help to download and run EtreCheck, written by a long-time forum member. The free version is fine. Post the full report using the Additional Text button. No personal information is revealed. 

Your CPU/memory usage are fine. However, you have only 35 GB of free space on your Mac, and that’s generally not sufficient. The absolute minimum is ~30-40 GB free space, and as a rule of thumb you should aim to have 15-20% of your total internal storage as free space.

Some steps to take to safely free up space:

Free up storage space on Mac - Apple Support

Optimize storage space on your Mac - Apple Support

How to free up ‘System Data’ and other st… - Apple Community