I recently bought the camera with the bell and wanted to offer the solution that worked after a lot of troubleshooting and research problems with my electrician. Background – I installed a fresh ringtone (there are no existing wires) and it didn’t work when I connected it normally without the sound kit. It still provides a series of flashing lights and will never connect. The solution to make the bell work well without the bell is to do the following. ** Buy one or select 16V (if variable … 24V is actually problematic) on the bell transformer. Connect one output leg from the transformer to the device, connect the other leg to terminal 2 of the sound unit, connect terminal 3 of the sound unit to the device. Set the bell unit control to the center off position. ** I plan to ring the bell through speakers connected to the homekit and I don’t need a bell. Everything works well, the motion sensor, the camera, the bell, etc. all are exposed by homekit. I removed it from this thread to provide adequate credit, but the tread is closed, so I couldn’t support this solution.