Applies to

• Red Range — Red 4 Pre, Red 8 Pre, Red 8 Line, Red 16 Line
• Clarett Thunderbolt

Overview

On some Macs running macOS Sequoia 15.x the Focusrite Thunderbolt driver fails to load. The interface shows in System Information > Thunderbolt but not in System Information > Audio, so no audio device is created.

1) Confirm that you have the issue

1. Power on the interface and connect it via Thunderbolt.
2. Hold the Option key and choose  Apple menu > System Information.
3. All four statements below must be true:

Audio device

Your interface DOES NOT appear as an audio device

Thunderbolt
Your interface DOES appear under Thunderbolt

Disabled Software
Our Thunderbolt Driver com.focusrite.driver.FocusritePCIe DOES NOT appear

Extensions 
Our Thunderbolt Driver com.focusrite.driver.FocusritePCIe DOES appear

If any statement is false you may have a different issue. Please contact Focusrite Technical Support.

2) Resolution: reinstall driver and rebuild kextcache

This process requires several restarts. Follow the steps in order.

2.1 Temporarily return macOS to “Full Security”

1. Boot into Recovery Mode.
   • Apple Silicon: shut down, then press and hold the power button until “Loading startup options” appears.
   • Intel: restart and hold Command + R.
2. Select the startup disk, choose your user, and enter the password.
3. Choose Utilities > Startup Security Utility.
4. Under Security Policy select Full Security.
5. Restart the Mac.
6. Ignore any driver warnings, then shut down the Mac.

2.2 Lower security to allow third-party kernel extensions

1. Boot into Recovery Mode again.
2. In Startup Security Utility select:
   • Reduced Security
   • “Allow user management of kernel extensions from identified developers”.
3. Restart and log in.

2.3 Install the latest Focusrite driver

1. Run the installer for your interface.
2. Open System Settings > Privacy & Security and click Allow when prompted, then restart the Mac.

2.4 Disable SIP, rebuild the kext cache, then re-enable SIP

1. Disable SIP
   Boot to Recovery Mode, open Terminal, and run:

   csrutil disable

   Restart normally.

2. Rebuild kextcache
   Open Terminal and run:

   sudo chmod -Rf 755 /S*/L*/E*
   sudo chmod -Rf 755 /L*/E*
   sudo chown -Rf 0:0 /S*/L*/E*
   sudo chown -Rf 0:0 /L*/E*
   
   sudo kextcache -i /

   Restart when the command completes.

3. Re-enable SIP
   Boot to Recovery Mode, open Terminal, and run:

   csrutil enable

   Restart once more.

3) Still not working?

If the interface is still missing from System Information > Audio, contact Focusrite Technical Support and include:

• Your macOS Sequoia version (for example 15.0.2)
• A fresh System Information report saved as .spx
• Details of the steps you have followed