Here's a somewhat recent personal project of mine. I'll have instructions and code online in a week or 2. The code has an adjustable delay to compensate for the software buffer and also distance from speakers to audience. This was supposed to be an easy project, but I ran into some surprising issues like the need for significant delay and writing code for that, and my desktop computer was creating a ground loop even though the power supplies for the LED's were supposedly isolated. Using a laptop solved that.