LG K5: 'The file format is not supported'

You want to listen to your mp3 files and just get the error message 'The file format is not supported'? Here's why!

If you are using the LG K5 you get to a point where the local storage is getting close.

To make up at least a little more space you may try to disable some Google services like Google Play Movies.

Interestingly, the internal music player is some sort of connection to Google Play Music. Therefore as soon as you disable this Google app you can no longer listen to mp3 files! So that´s a service you need to let keep running.

So... just let it run...