Code to play sound in axapta 
 static void ExemploPlaySound(Args _args)  
 {  
   System.Media.SoundPlayer YourMPlayer;  
   ;  
   YourMPlayer= new System.Media.SoundPlayer();  
   YourMPlayer.set_SoundLocation("c:\\xyz.wav");  
   YourMPlayer.Play();  
 }  
