Media.getDuration() sometimes doesn't get the right duration on iOS

Hi,
I have an audioguide app, where i store audio and images directly on the phone. I store and then get the files with the cordova file plugin, and load it with cordova plugin media.
On some tours, the duration gets multiplied by about 1,835 (i'm talking about the value i get directly from the media.getDuration() function), and on the other, the duration is just right.
The issue only happens on iOS, it works perfectly fine on Android.
I have no idea how you could recreate the bug.

Thanks