It had been quite a long time since I last (and first) configured my PSP. It is running under the M33 firmware and for unknown reasons, my memory card lost all my ISO and CSO games including the saved game files. I did manage to backup before but my Indiana Jones Adventures saved game was lost forever. Anyway, when I copied my games to my memory stick, I found out that the games loaded slow. Seemed my configurations got changed too. To go to the recovery configuration menu, turn off your PSP then turn it back one while you are pressing R.
Once in the recovery menu, make sure you set the following.
– Configuration > UMD Mode > choose sony np9660 -NO-UMD-
– Configuration > set use vshmenu to enabled
– Go back to the menu and then choose cpu speed. change the umd/iso speed by pressing the button X. Keep on pressing X until you see it set to 300-
– Go back to the main menu and choose exit.
Your game should be running smoothly then.