PocketMatrix

When you turn your PPC on, when the game becomes "sluggish", go to the settings -> system -> memory applet, and check out what is running in the "running programs".

If you don't have anything there, is the game on a storage card? If so, some cards take some time to initialize due to the security features.

Also, if you have a jacket with your PPC, you might get a slow down when turning on the PPC, until the jacket is detected and properly initialized.

Then, I would suggest to do a cold start (delete everything), copy just the game back and try it. Maybe some other programs has fucked up windows.

Lastly, if the problem persists, check your code

--Eric