Missing text on firmware 2.0 update

Hi there

I have a UK psp. I have been running 1.5, whilst usingWAB changer to trick the sytem into thinking its running 2.0. I switched WAB back to 1.5 so I could actually update the firmware to 2.0. I select 2.0 on the PSP demo disc that came with the system, and I get the screen with the options to press X or O, but the text that is supposed to be there is missing. I'm guessing its something to do with WAB, as i've googled this and heard of other people having the problem (but couldnt find any answers) after using WAB changer.

Any ideas on how to get around this?


Cheers