I have the same one. It uses a sinowealth chip and samsung memory. The reason it is fading is the thing needs charged. To properly charge it, turn it off, plug it into the USB port, and then flip the switch to on. The led should turn on afterwards. I went through a painstaking process today involving a voltmeter to test output. This model doesn't charge properly without following the process above. It is a fake shuffle model.
My daughter used it one time and after a charge, it would not play longer than 2 minutes. After following my charging process, it is working fine. If it was like ours, it came with no manual. Its like a $10 mp3 player off of ebay.
If you wish to test, disassemble and put voltmetet leads on the tabs coming off the battery. With the USB plugged in you should read 3.5V. When I played and let it fade, the output dropped to <1V. Charging correctly did the trick.
