Ok, Scroll down this post and I have written a walkthrough of how I recovered a player by shorting the main chip.
http://www.mympxplayer.com/viewtopic...r=asc&&start=0
I suggest once your player is recognised as a ADFU device you reflash with 3.5.37v2.1b FM.fw
Which should partially recover it, it will still have a black screen. Do not disconnect it leave it for about 30sec then update it again with the one above. If it will not update leave it connected switch it off and then back on wait a few seconds then try again.
It should then reboot and be ok.