Phantom Doorbell

Ok folks, I’ve read the other threads and it seems like no one has gotten to the bottom of this yet. Here’s how it has been working for me - someone legitimately comes to the door and rings the bell. The bell chimes as expected. Then for the next half hour or so we get phantom chimes every so often. Almost like there is a capacitor somewhere that is getting charged up and then self discharges once it reaches a certain voltage. Eventually the phantom ringing stops. I do have a diode (1N4001) on my doorbell across the two terminals. Ok Eufy support - have at it!

Why the diode?