You may have seen the following message after launching Ecamm Live on macOS Sequoia:

This permission is required for Ecamm Live to work with NDI.
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If you’ve seen this prompt and have already chosen “Don’t Allow”, you can grant this permission by enabling the toggle next to Ecamm Live in the Privacy & Security control panel of your Mac’s System Settings application. You can find this under “Local Network” once you have selected Privacy & Security from the left.

If you're still having trouble with NDI after double-checking that this permission is enabled, check to make sure you are running Ecamm Live from your Mac's Applications folder and try again.
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