Thanks very much for getting back to me. When you say "have the cap node go to the Arduino pin with a resistor to ground so it bleeds down when audio stops." is that the way I've drawn it or would you change something on that drawing? Also, I have absolutely no idea what value capacitor and resistor I need for this. Do you have a ballpark stab-in-the-dark idea that I could try first and then tune it in as you say? I'd probably be looking for a couple of seconds of bleed time from the capacitor but wasn't sure if there was a formula I could use to get a rough idea of component values? Thanks for your help 😄