How to fade out audio on exit ?

[asper]

Can someone tell me how to fade out audio while using this code:


case WPAD_BUTTON_PLUS:
MP3Player_Stop();
ASND_End();
snprintf(filename, 128, folder "plus.elf");
break;

I think that a volume from X value to zero (before the MP3Player_Stop();) should be the right way but... how to implement that in C code ?