Check your sound settings

• In [Settings] > [Sound & Vibration], drag the Ringer and Media Volume sliders to the right to rise the volume.
• Go to [Settings] > [Do Not Disturb] and check that Do Not Disturb is off.

Clean phone speakers

• The receiver won’t work properly if it’s blocked or dirty. Clean the receiver with a clean and soft-bristled brush or cotton bud.

• Make sure nothing is blocking the receiver, such as a phone case, or your fingers. Metal phone case can affect the degree of cell phone signal reception. Remove the phone case or screen protector that might block the receiver, then test again.
• When you’re on a call, keep your mouth close to the speaker openings to ensure the call quality.

Check the connected accessories

​If your OPPO phone is connected to a headset, make sure it is plugged in firmly. If a Bluetooth headset is connected, go to [Settings] > [Bluetooth] and reconnect the headset.

Plug headphones into your phone

If you can hear sound through the headphones but not through your phone’s speakers, unplug the headphones and test again.

Restart and update the phone

​Restart the phone, and make sure you have the latest software version.

Other issues

• If you cannot hear a specific person’s voice clearly, it might be his/her phone’s issue.
• Consult with your network operator for the network issues.

If the following steps did not resolve the issue, kindly contact OPPO Support Team, or take your phone, proof of purchase and warranty card to a nearby OPPO Customer Service Center.