Thank you all for reporting this and we are sorry for the issues this problem is causing. We are aware of this issue on macOS Sequoia which affects some Mac systems and some Focusrite interfaces which use Focusrite Control. There seems to be no specific correlation between Mac model and the issue as when testing on multiple identical systems the issue has not occurred on both Macs.
The issue seems to be that the Mac system can not or will not detect the interface as an audio device when it is connected to the Mac during a restart or boot-up up but it will still detect the unit on a hardware level in the USB device tree on the mac.
Our software and QA teams are investigating the causes of this issue so that this can be fixed and we will update this thread, our macOS Compatibility article as well as any customers who have reported this issue via email to our support teams once the issue is resolved.
In the meantime we recommend that Solo and 2i2 customers uninstall Focusrite Control from their system as all of the functions in the control software can be done from the front panel of the device or through other apps on the Mac. - How to uninstall Focusrite Control from your computer
For all other affected customers you will need to either unplug the USB cable from the interface or Mac and then reconnect this after your Mac has booted and you are logged in, or if you have a mains-powered interface turn the device off and back on after your mac has booted and you are logged in.
-Focusrite