I hear the things I like about the DS and DS Jr right out of the box. Some others don’t like the sound as much out of the box.
When I had my very burned in test DS and got another new one the new one sounded covered, muffled and a little dull. I let it play continuously for a week or two and then it sounded much better. The bass firmed up, the top opened up the presentation got more balanced, etc.