Basically, this is like Release Delay but for before you start speaking.
There are no free utlities that do everything AutoPTT does.
Sure, if all you need is a system-wide Push-to-Mute or a Toggle Mute, you might be able to use a free utility for it. On the other hand, AutoPTT has a number of unique features that other apps do not offer, such as:
Unless you want to use activation modes other than PTT where only PTT is allowed (eg. with Priority Speaker, or in channels with forced PTT), AutoPTT probably isn't that useful for you. It's mainly meant for ingame voice chat, which koften lacks features.
Of course, AutoPTT does have other unique features that may still be useful with Discord and Teamspeak. See the answer to the previous question for some examples.
No. Plenty of software listens for (and generates) input events. For example, if you have a gaming mouse and you remap a button to a keyboard key, it's likely done the same way AutoPTT does.
If you're buying multiple licenses, sure. Get in touch.
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