1. If you are using only one earbud for the call, ensure the other earbud is in the charging case with the lid closed.

2. Replace the ear wings/ear tips with a better-fitting size. Check the L/R marks on the back of the earbuds and ensure they are worn on the corresponding sides, and that they are positioned well for a tight seal for the best call quality.

3. Ensure the connected device has "soundcore Liberty 5 Pro Max" set as the audio output device.

4. Switch between the phone microphone and earbud microphone to see if voice quality improves.

5. If you are using a third-party app (not the phone's system phone app) for calls, try making a standard phone call via the default app to see if the issue persists.

6. Test calls using the earbuds in a quiet environment to see if the issue persists.

If you encounter any other issues or your issue has not been resolved, please contact us for further assistance.