That’s easy, just add following code in your theme’s functions.php file:
function 348118_my_home_category( $query ) {
if ( $query->is_home() && $query->is_main_query() ) {
$query->set( 'cat', '1234' );
}
}
add_action( 'pre_get_posts', '348118_my_home_category' );
In the above code change 1234 with the ID of your music category.