The sound from the speaker is distorted.

Adjust the playback volume.

Make sure the tablet is sufficiently charged.

If the sound effects are turned off, the sound might improve.

Tap [ Apps & Widgets] - [ Settings] - [Sound] - [Sound enhancements] - [Settings] - [xLOUD(TM)] or [Clear Phase(TM)] to remove the check mark from the box for that setting.