I've tried many versions and I've altered my firmware to be compatible with my various versions I try. Finally I gave up, updated to 5.00 M33-4 again, and tried the Music.prx compatible with every M33 firmware 3.90 M33+. I've followed steps exactly by several how to videos. I managed to get the Music.prx menu up in XMB and UMD, but instead of the text that shouldve been there in the menu, it was a screwed up mess saying something about a "root directory ms0:/PSP..." being empty. I have no idea what I screwed up. Anyone know what to do?