“Enable charging case sounds” is greyed oit

I had the same thing, after following some other posts that said I should forget it and then resync it to the phone (which didn't work) I found when I plugged the case in for charging with the ipods in it, that setting wasn't grayed out anymore and I was able to change it to off. (finally!)

Same problem here. I also have an iPhone 11 with 2nd gen. AirPods Pro. I've tried "forgetting" and re-syncing the AirPods, but that did not work. Neither did shutting down and rebooting my phone. Also, plugging in the case with the AirPods in them did not work for me either.

It's frustrating, especially when the chimes go off at seemingly random and very inconvenient times.