I am convinced that this is a software issue.

Hi, recently my PSP's home button and volume buttons have stopped working, the volume is stuck on full blast, and my home button no longer does anything, but the strange thing is, the display (brightness) button works as a home button.
My PSP is about 3-4 years old, and this is the only problem I have ever had with it. I am running 5.50 Gen d-3, and when I open the VSH menu, I cannot exit, as it will freeze my PSP's XMB.
I have already downgraded to 5.00 m33-6 w/hell cats recovery flahser, The VSH menu still froze :(. I have also tried disabling VSH menu, that did nothing, and using the hold button did nothing.
Chilly Willy's key cleaner says I have O.K. keys.
I have opened my PSP up, and there seems to be no dust etc. on the buttons/connection ribbon cable. I cannot use the buttons when it is opened up either.
I have formatted flash0 and nothing changed.
I cannot buy a new PCB bar on E-bay as I do not have a credit card/paypal.

I have not dropped my PSP!