There's a good chance that it has a SigmaTel chipset -- search for threads on this site re Matsui players and follow links to a firmware extractor. It may not work of course, but should do no harm.
Beyond that your best bet is to post a picture of the device on this site (and perhaps on www.anythingbutipod.com) and see if anyone recognises it.
Frankly, most unbranded players are a pain to use, anyway.
I bought a mp3 player a year back. Its not a branded one. And also I'm not able to find out which chip is used in it. It keeps giving me firmware problem and every time i should get it serviced for which I'm charged a lot. So if i can have a copy of the firmware with me i can re-install when ever this problem surfaces. I searched the net and found that there are lot of firmware extractors. But I'm not sure which one will work properly on mine as i do not know which brand is mine. So please help me find a extractor which can work on any mp3 player without any problem.

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