Does anyone know if there's a way to adjust the calibration of the G's nav system? Some Acuras and others have a "secret menu" that allows tweaking such settings.

The nav in my 2003.5 6MT sedan shows me consistently about 100-150ft behind where I actually am. I've tried the adjust position feature, but that only helps for a short time.

I have the stock tire/wheel set up for the vehicle, and have no mods except for the PA-11NIS ipod controller.