An apparent bug in macOS Monterey causes a 1-2 second video delay when USB webcams such as the Logitech Brio run in 4K mode. The issue is not specific to Ecamm Live.

Currently the only workaround that we have for this issue is to set your Ecamm Live Stream Size setting to 1080p instead of 4K.

If the webcam is still running in 4K mode after changing the Stream Size, ensure that the Use Maximum Resolution checkbox is not checked in the Camera Effects window.