In the past I’ve used Shush to achieve a push-to-talk or push-to-silence setup on my Mac. It works alright but more often than not I forget which mode I’m in, or whether I’m silenced or not. This leads to awkward moments in meetings.
I’ve solved the problem using Keyboard Maestro. This macro, triggered via CTRL-m simple enables or disables the current “input” device (whatever is selected in the Sound preferences) by setting its level to 0 or 100. It’s a toggling macro so you can use the same hotkey to flip between the two states. Most importantly, though, is the nice popup alert that appears when you go into “disabled” mic mode. This window is hide-able if it gets in the way, and it also disappears if you re-enable (via hotkey OR the RE-ENABLE button). You can safely disable the “Custom HTML Prompt” action if you don’t want to see the prompt. Here’s what the popup looks like: