i'd might be possible in dingux. the rootfs has two commandline mp3 player on board. madplay and mpg123. madplay uses less cpu power than mpg123. You could write a sh script and use nohub and & to pipe this in the background. then start your emulator.
but thats all theory. i haven't tested this yet.
Your theory is correct.
Tested with both, but only madplay worked, and its block all the emulator(in snes9x) sound, so the only thing who plays is the .mp3.
Tested with quakux and Snes9x and the mp3 runs smoothly while playing and while entering and leaving the app, without any problem or slowdown.
@ ClaasClever:The command batch I used:
#!/bin/sh
cd /usr/local/apps
nohup madplay -Q sound_of_my_dream.mp3 &
"#!/bin/sh" is Linux bullshit, so don't change it.
"cd /usr/local/apps" is the place where the music was, so change "local/apps" to the folder where your music is.
nohup madplay -Q sound_of_my_dream.mp3 &" is the music config, change "sound_of_my_dream.mp3" to your music name, it can accept more than one input file, just add a space between each music name, and switch the spaces to underlines in the music names or some error can happen.
http://linuxmanpages.com/man1/madplay.1.phpIf using gmenu, after create the link to the batch don't forget to edit the link with sound!
And the batch need be done in Linux text type, so if in windows, use a win2lin converter before to put in the sd card.
PS:This don't play without the -Q option, so I think the mpg123 didn't worked cause some error in the command I used.
mog edit:To clarify, you need to save the quote text as a bash script (filename.sh), put it in your /local/ folder, and then either add it to gmenu or launch it with telnet.