Press the volume up button a few times first. Check to make sure you are not in a muted or do not disturb mode. Check the speakers through diagnostics in Sonim Scout.
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.