I have had this doorbell installed for almost a year. The other night it began to constantly ring until I unhooked the wiring to the hallway chime. It is as if the doorbell is completing the circuit internally. All my wiring is good, no shorts. Switched locations with another doorbell and it caused the same issue at that location. Does this Ring doorbell just need to be replaced after only a year?
Although you’ve had this Doorbell installed for some time, I recommend checking the compatibility of the chime kit being used, just to ensure it is intended to work with your Video Doorbell. Try also checking wiring for any corrosion, debris, or any other issues that might cause this.
In your Ring app you can also choose the chime type via the Video Doorbell Device Settings > General Settings. I hope this helps! 
My hardwired ring doorbell pro did the same thing ( ring every 15, 30 seconds or so) two nights ago at 11:49 pm, and I had to cut the power at the transformer.
Hooked it up 12 hours later, re-initiated it, and two days later it has not repeated the problem.
Ps. The power bypasses the old mechanical doorbell.
There us no debris or corrosion and it’s been working fine for over two years!