[yocto] Media players: recipes and packages

[Jose Mª Ferreiro]

Hello

Here is: iMX6 Sabre Lite + Yocto dylan

We want to reproduce some music and video files to test the board 
behaviour.

With fsl-image-gui:
   - Video player: a mp4 file is well reproduced. Image is good. Sound 
is low but I can hear it with headphones connected to board.
   - Music player: when we select a mp3 file, the window closes

With core-image-sato-sdk:
   - Video player: when we select a mp4 file, an error comes: a plug-in 
is needed
   - Music player: when we select a mp3 file, the player shows it, but 
the play does not start

How can I find what package/recipe in fsl-image-gui does mp4 work?
Is there any way to know what kind of files can play each image by default?

Thanks,
Jose