It should play all 3 types of files. I'm guessing that they used the term "support" when referring to wav files because there's very few people out there who would use it to play wav files due to their size. As long as it plays mp3 and wma files you'll be fine. Just out of curiousity, what player are you looking at?
I think that the human mind is unique among all other forms of life in that it can spontaneously create unique thoughts and provide unique behaviors. Instead of rewarding that uniqueness we, for some reason probably because of cultural and social necessity, we chastise unique behavior and reward conformity.
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