Well, in fact IrrlichtX is one of the most recent contributions to the Xbox scene, so the problem with it, is not that the code is old (this can happen with other Xbox homebrew games). The problem is the opposite: there is still almost no code done for IrrlichtX for Xbox.
But if you download IrrlichtX, you will see some easy samples there to begin with. Or you can go to the official Irrlicht page (not the Xbox one) and begin with the samples there. Remember that even those Irrlicht samples for Windows, can be used with the Xbox IrrlichtX!! You only must keep in mind a few things, for example in Xbox there is no "caption of the window" because the application is allways fullscreen, so it has no sense to call an Irrlicht function that writes the caption of the window, and that code must be erased from the samples.
As far as the sound issue... you can use SDL for sound! SDL is not only about 2D graphics, it also gives you support for audio, joypad control, and so on... I mean, use IrrlichtX for the graphics and SDLx for the sound. In fact, the code of the sound in a videogame is very short, mainly begin a song at the begining of a stage, finish a sond at the end, play a wav file when you shoot... This code is very easy with SDL. You can see the tutorials of Lazyfoo here about SDL:
http://lazyfoo.net/SDL_tutorials/index.php (see Lesson 11 for sound)
And if you get stuck, you can ask for help (IMG:
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