1.If it is recognised as two devices you need to fowlow some steps to repair that in here:
http://www.mympxplayer.org/how-to-re...ck-vt2400.html.
2.Black screen is strange... Does your mp5 have a reset button or a connectable battery that you can put off and back there to reset your player ?
3. seems it is confused someway... try what i said and if not working wire here... we will alk about what next.. Dont yet try to repair your firmware and if read all the articles about it... dont upload any new !
also look for forums of your provider to search if no1 has the same problem...