Different earnings on same console, same level

[rechtepasta]

When we first bought our PSP a few months ago, one of the first games we bought was need for speed. Both me (adult) and my son are enjoying this game. We both started in easy mode, and are getting more experienced along the way.

There is a strange thing though .. for some races I can earn up to $15.000, while the maximum my son can earn almost half of it. I understand this because we are both on the same console, so we have the same software version.

Any help would be appreciated. Thanks!