Diagnosis
The device is receiving the alert signal but the audio output is muted or the volume is set to zero. This is a software setting issue.
How to Fix It
Open the Ring app. Go to the Chime Pro device tile. Tap on Audio Settings. First, check the volume slider. Ensure it is not at the minimum. Second, verify the selected chime tone. Test it by tapping 'Play Sound'. Third, check the 'Do Not Disturb' schedule. If enabled, it will silence the chime during scheduled hours.
If That Didn't Work
The audio hardware may be in a soft-lock state. Perform a reboot. Unplug the Chime Pro from power for 30 seconds. Plug it back in. Wait for it to fully reconnect (light is off). Test the sound again using the 'Play Sound' button in the app.
Heads Up
If you have multiple Chime Pros or a Ring Alarm Base Station, check the linked device settings. An alert sent to another device may be configured to silence alerts on the Chime Pro.