1. Ensure that you have the latest software version of your phone
2. Check your coverage area to make sure the best signal is available
3. Set your volume gearing level to the highest setting
4. Try placing your call in speaker mode
5. Ensure your phone is securely connected to the charging port
6. Reset the network settings on your phone
7. Move closer to building windows or outside to increase signal
8. Try contacting your network provider for additional support