J-M-L:
No I’m saying that when you have code depending on proper timing and interrupts but have too many interrupts going on (interrupts are not interrupted) then you can get in troubleIs the code working if you don’t play with the leds or pretend with the fastLED library (which I assume you use) that you have APA102 connected instead of your WS2812B?
The code is working if either I exclude the MP3 or the LED. Unfortunately, I do not have the APA102. I only have the WS2812B. The only interrupts I may be using is the EVERY_N_MILLISECONDS function. The rest are through using if/else statements.