The Blackmagic UltraStudio Recorder 3G may not be recognized by the Desktop Video Setup application. If it's not recognized there, Focus Server won't recognize it either.
Expected Behaviour
When your Blackmagic UltraStudio Recorder 3G device is plugged in and recognized, you should see the device populate in Desktop Video Setup.
Resolution Steps
Drop the Startup Security setting to "Reduced" by following this guide - https://support.apple.com/guide/mac-help/change-security-settings-startup-disk-a-mac-mchl768f7291/mac
If you’re the administrator of the Mac, you can change the level of security used on your startup disk.
- On the Mac with Apple silicon, choose Apple menu > Shut Down.
- Press and hold the power button until “Loading startup options” appears.
- Click Options, then click Continue.
- Select a startup disk, then click Next.
- Select an administrator account, then click Next.
- Enter the password for the administrator account, then click Continue.
- In the Recovery app, choose Utilities from the upper toolbar > Startup Security Utility.
- Select the system you want to use to set the security policy.
- If the disk is encrypted with FileVault, click Unlock, enter the password, then click Unlock.
- Click Security Policy.
- Select Reduced Security: Allows any version of signed operating system software ever trusted by Apple to run.
- Tick the box for Allow user management of kernel extensions from identified developers.
- Click OK.
- Choose Apple menu > Restart.
You must restart your Mac for the changes to take effect