No, will probably never happen.

 

The DS doesn't have an operating system running in the background, so once you load a *.nds file, whatever was previously loaded gets shut out of memory. So no, you can't run a media player and a game simultaneously.

 

It's worth noting that DSLinux is capable of multitasking if you have slot-2 RAM available. In one virtual shell I can play back some mp3 files while I browse the web in another shell and type on IRC in a third. Of course the music gets choppy whenever I load a webpage since the DS isn't really powerful enough to handle it gracefully, but the fact remains that it's possible.

 

The DSLinux Wiki would be a good place to start. Also note that you'd want the DLDI build, not the .nds build.

 

Would it be possible to change the game's music to your own?

 

My speakers are just fine. After doing, maybe 7 tests of it. The speakers are fine. I don't understand how it can fry the speakers if you're just inputting sound from a source. That's like putting in a DS Headset with a Microphone, and blowing in the microphone and the DS reads it.

But overall, my DS Phat is dead due to some F2 fuse problems. Also some screen problems as well.