I too am struggling with the same problem on newly purchased Doorbell Pro (12/28/2019). I am using a Samsung S8 and individuals can hear me from the Doorbell clearly but I can’t hear them. I can hear audio from the stored or recorded “live view” captures but none “live” or after ringing the doorbell for a two-way communication. Voltage is GOOD, Signal Strength is RSSI-54 and clean bill of health from Device Health Report. Everything else appears to be fine EXCEPT Live audio functionality and sometime live doesn’t connect. Frustrating! I am using this device to monitor my elderly mothers home!
App version 3.21.1