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?

Hi @user24892. The chime kit shouldn’t be making a buzzing noise, but you can find steps on how to bypass your internal chime kit with the Pro Power Kit v2 here. Bypassing the chime kit, since you do not want to utilize it, may resolve the buzzing noise.

As for the wiring setup, you can find various wiring diagrams in our Help Center article here. That should help you determine the correct setup based on how many internal chimes you have. It’s important to note that the Pro Power Kit v2 should be installed for each Doorbell Pro you’re installing. I hope this helps