This is an unusual player!.
If the firmware is working ok then it might be better to just change say the English language to German.
It may not be possible to find another firmware for this player, you could try looking in the
http://www.s1fw.com/ database but it might brick your player.
The tool to change languages is here:-
http://www.mympxplayer.org/tool-rock...ngs-df691.html