The last 3 releases included many code improvements with some of the old Objective-C modules completely re-written in Swift.
V2.25 provides the ability to set specific audio devices for use with EchoHam via the preferences window.
Since some audio devices can be temporary (e.g. bluetooth earphones getting disconnected), EchoHam will not complain when a pre-set audio device is not available, instead, it will revert to the default device specified in system preferences.
To always use the audio settings from system preferences you can set the audio devices to "Default" in EchoHam.
Using default devices has the advantage of devices automatically changing as required by the system.