I just installed my Ring Video Doorbell Pro onto an existing wired digital doorbell. The exterior button had a diode to extend the ring time 6-7 seconds (it has a very pretentious ring), but installing the Ring Doorbell with the diode resulted in continuous ringing. Without the diode, the interior doorbell wouldn’t ring at all.
I ended up installing the Ring Doorbell without the diode and started reading help entries on the Ring site to find a solution. After 30 minutes I found the answer (which isn’t in any of the official help menus). The Ring Doorbell Pro has an internal diode, so take the diode out when you install the Ring Doorbell. On your cell phone, in General Settings, go to the Internal Doorbell Setting section and touch “Doorbell Chime Type.” Select “digital” “Ring my in-home doorbell” and set the “Ring tone length” and save. It took a couple tries to get the right number of seconds, but my interior doorbell is ringing perfectly! Opa!