background music player

Using the ds as an mp3 player is pretty kool, playing ds roms and old school system roms is pretty kool as well. What I would ABSOLUTELY love is playing my all time favorite games WHILST listening to my all time favorite music. Sure I can listen to music on my computer whilst I play ds but I almost never play ds at home, I like having it on the go. Would it be possible to cut off any other type of sound when playing music with that program (i.e. only make sound from the mp3 file instead of the nds file) or maybe even better having the option of turning off the game's music but keeping the sound effects (which I think that option is on alot of nds games anyways). I'm not sure if I explained this all to well so Ill give an example of what it would be like...I am using an R4DS btw

I would load up R4DS and then click on the games category. Then I would load up the program (off the top of my head name) mp3 background player.nds. Then it will search through my micro sd card for all my mp3 files and put them into a playlist. After that it will begin playing the music and you can choose the game to play, in my case ill choose Touch the Dead. The program (mp3 background player) will cut off all sound from Touch the Dead.nds and only play the mp3 files from the playlist. I hope that made a lil more sense.

No that wont work the mp3 player is a standalone app built into r4ds firmware when you go to run a game the mp3 player is terminated and no loner running. The DS is not like a Computer OS it can not multi task like linux / mac os / windows.

Right, the DS has no operating system like the PSP does. Once a program has control over the system, the previous program is terminated and the new program has full control over the entire system. There's no way to do what you're asking, at least not easily.