Press volume up. Check the headset settings in your Bluetooth menu to ensure audio is enabled. Pair your phone and headset and try again.
If you need any further assistance with this question, please contact the Sonim Customer Experience Center at 1-833-MY-SONIM (1-833-697-6646) or email us at [email protected]. We are open 24 hours a day, Monday-Friday and we will further assist in troubleshooting.