To ensure your PowerPoint presentation plays looping background music:

1. Check your powerpoint version – Make sure you PowerPoint version is recent enough to support audio files.


2. Check your audio file format – MAKE sure your audio file is in a compatible format, such as MP3 or WAV.


3. Check your sound settings – Make sure your sound settings are enabled and at the correct level.


4. Check to make sure you have added the audio file to your presentation – Make sure you have inserted the audio file into your presentation, either from the Insert tab or from the Media tab.


5. Set the audio file to loop – Make sure you have the option to 'Loop until stopped' selected when playing the audio file.