It's normal to listen to music on your mobile phone, and watch videos. I don't know what's going on.

When playing video and music on the mobile phone, if the sound automatically becomes smaller, it is suggested that:

1. Make sure to use the video/music player that comes with your phone.

2. Play the video or music on the computer and check whether the file is normal.

3. Record an audio or video with the camera or tape recorder that comes with the mobile phone to check whether it is normal.

4. Uninstall the recently installed software.

5. If the above operations cannot be played normally, please back up important data and restore the phone to factory settings.