Achievement Walkthrough

[Daggermn]

Hey guys. Any help you can give would be appreciated. I have gone through the game using the guide and I unlocked all achievements except for the achievement called 混沌の詩. I believe this is the achievement for listening to the 2 songs, but after following the guide again up to this point, I am not getting the achievement. Is there something I'm missing? I've listened to the songs for a long time and still no achievement. I did a Google Translate on the achievement details and it mentions something with 4 songs. Can someone help me out? Thanks again.