MediaContainer music = new MediaContainer( "canon.wav" );
. . .
TransformGroup group = new TransformGroup( );
. . .
BackgroundSound sound = new BackgroundSound( );
sound.setSoundData( music );
sound.setInitialGain( 1.0f );
sound.setEnable( true );
sound.setLoop( -1 );     // Loop forever
. . .
sound.setSchedulingBounds( bounds );
group.addChild( sound );