Hello there, as state Lolita, you must use S1Clone, but S1Clone will be able only to make a backup of your firmware, the firmware can't be etracted and the result file can't be used to firmware modifications.
Reading your problem is very like you have a hacked player you shuld follow the guide "How To: Removing Memory Hack "
http://mympxplayer.org//how-to-remov...ck-vt2400.html How To Remove Memory Hack This procedure is very safe the only harm could be you get less memory, you can contact the saller to inform this and get a refund.