Well for everyone who doesn't know what this is, it is a PRX that allows you to listen to your saved music anytime. That is right, including IN GAME. 

Cpasjuste has recently ported the Music PRX plugin to custom firmware 3.90 M33. Enjoy your own MP3s and atrac3 files straight from your memory stick’s MUSIC directory. Cpasjuste also notes,

“this has been tested on a 3.90 M33-3 slim PSP, WITHOUT the fatmsmod patch applied.”

If you are using a lower firmware please upgrade.

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