Madplay allows you to play a MP3 in the background.
Release notes:
Place the scripts somewhere on your SD-Card and add them in Gmenu2x.
You need to set “DON’T Leave” Option on the Icon of the “madplay_play.sh” Script! But only there! Otherwise it won’t play.
http://sience.schattenkind.net/dingoo/madplay_background.zip
Source
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