Why is two player option gone ?

[mccauley]

I have a PS 9000series, so I was told I had to
get a chip in, rather than the external one. Since it was installed, none of our
games (original or backup) will let us play the
two player option, which is annoying for race
games. Do I need to patch them? We called the
guy who installed it and he said he's never heard
of this.

Thanks to anyone who can help.

(games tried so far are Toy Story Racer, moto cross, Star wars, and a few more)