The possibility is that you may have got the player bricked. Or may be it has become slow due to all the memory filled up. The reason why these Chinese Devices aren't trusted is because these don't come with a warranty. The only difference between branded products and unbranded one is service. I think no way out but to dump this device. OR, may be try to reset it. Try googling how to hard reset this device. But again the problem is how will the computer detect it as it isn't powering itself up.
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