Ring Doorbell 3 Device Audio Volume Adjustment

Just purchased the Ring Doorbell 3 for my office. Replaced the original Ring Doorbell that had echoing and audio dropping problems. This device is working fine, but the customer needs to hold his ear up to the device to hear what the receptionist is saying. It's too quiet. The chime / ring volume is fine (if not too loud... working on it). We can hear the customer fine.How can I adjust the volumen of the Ring Unit itself? It needs to be louder!