Looking to install two ring doorbell pro

Setup by the builder: 2 nutone doorbell 1 mechanical chime box (both doorbells are connected to this chime box) 1 transformer (Transformer is NuTone C907 16V, 30Va) I attempted to install one of the Ring Doorbell Prob last night. See chime picture here, you can see I have the Pro Power Kit v2 connected. Everything is working properly, but there’s a small buzzing noise coming out of the chime and also the circuit breaker. Called Ring support and they suggested I remove the Pro Power Kit v2 from the chime, and it’s making a even louder buzzing noise. I know the Doorbell Pro supports ringing in my mechanical chime, but I actually don’t want that. I bought multiple Chime pro already. Two questions: 1) is the buzzing noise a concern? How to get rid of it? 2) does my existing setup work with a second ring doorbell pro. Do I need a different transformer? Would I need two. Power pack installed to the chime? 3) since I don’t need the mechanical chime to work, is there some steps I can bypass and not rely on it?