Today the state is (almost) as it always was: 1. Install and set up JACK. Enjoy your lack of latency. I haven't profiled it scientifically, but I've tried micr

Today the state is (almost) as it always was: 1. Install and set up JACK. Enjoy your lack of latency. I haven't profiled it scientifically, but I've tried microphone monitoring with filters layered on and couldn't detect any latency between me speaking and my voice coming out the speakers. 2. Modern linux uses pulse. Pulse is kind of jingoist and slightly hostile to foreign presence. You'll need to edit its default.pa file to not load the udev-detect module and not try to just grab the soundcard for itself, but to load the jack-source and jack-sink modules. You'll also need to write a script to do the module loading because modern desktop linux doesn't have a race-free way to start daemons when a user logs in. Which you'll have to run manually once you log in. That script looks like this: #!/usr/bin/sh pacmd load-module module-jack-source channels=1 pacmd load-module module-jack-sink channels=2 Oh, and if it wasn't apparent, only one user can use the audio.