Test the project: https://bukmand.itch.io/simple-online-voice-chat-gamemaker-source-code
Marketplace don't show 2.3, you can download from GMS IDE library.
Voice chat between 2 clients or more.
Tested on Windows 10
How to use:
Press enter to choose your microphone.
Press C to connect to your server.
Hold space to voice chat.
Press 1, 2 or 3 to select chat room.
Works Online if you portforward.
Made with default GMS2 networking
If you have any trouble hearing voice in GMS2, export project to exe, run and it should work fine.
Fixed a bug with online players
Slightly fixed CPU usage
Added online test to itch.io
Fixed stutter bug, added audio compression