Wrong length displayed for audio file

So I have an audio book in a single mp3 file that's over 5 hours long. On my computer all players display it's length correctly, however on my phone [Smart AudioBook Player](https://play.google.com/store/apps/details?id=ak.alizandro.smartaudiobookplayer) and the Play Music app both says that it's only 11 minutes long. Rockbox picks up the length correctly. What could be the problem and how can I fix it **without using a different app**?