mtschart , unfortunately the Samsung K9LAG08U0M is a 16Gigabit (2GigaByte) memory chip, and not a 4GB chip. Unless you have 2 of such chips on the player, else your player was a hacked 2GB player.
Your player would be using the v9.0.xx series firmwares here
http://www.mympxplayer.org/actions-9...mare-dc37.html
There is no way of telling which firmware would work, so you'll need to try all of them.
Good luck.