PSA: Even as of today, SP32 core 1.0.6 is required for this code - Symptoms of newer core versions include what appears to be (incorrectly) a hardware fault in the INMP441 mic.

[dustinsterk]

I failed to see the below notice and spent hours troubleshooting what I assumed was a bad INMP441 mic or faulty wiring/soldering. The symptoms included the levels/visuals bouncing whenever I touched the mic leads/wires/GND but would not register any audible noises when speaking close to the mic. It turns out my issue was software only, and I just needed to downgrade the ESP32 core to 1.0.6 and magically everything worked perfectly.

IMPORTANT: For now, the code will only work with ESP32 core 1.0.6, and is unreliable on 2.0.0. I'm thinking this is a FastLED issue, but I might be wrong on that! Use the boards manager to revert to 1.0.6 in order to compile and upload.