So you have just upgraded to 1.29 K, and when you turned it on the screen was full of Korean characters.
1.29 K is the first firmware to do this, and here is the solution.
Turn player on.
Hold (not press) the Navi button.
From the menu select the first option by just pressing (not holding) the Navi button.
Go to the second menu option by pressing the (-).
Then select that by pressing Navi.
Use the (+) to go up the options, until you see English.
Select that.
There you go
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