If you are annoyed by the intro music like I am. And really annoyed when you tick the box in options to mute it, and it doesn't mute at all. I have the solution.
Open C:\NTTGame\KnightOnlineEn\Snd folder. Rename two files by putting an x infront of them. The 2 music files used on the intro and character selections screen are: bless.ogg, intro_sound.ogg.
bless.ogg becomes xbless.ogg
intro_sound.ogg becomes xintro_sound.ogg
Log game with no music now
You could even put you own music file there, just rename it to bless.ogg, and for character screen music intro_sound.ogg.