Also remember that radio presets (and AC settings) are tied to driver memory settings. Did you program your memory settings and tie them to a keyfob? If not, and you are unlocking with the keyfob, you may be putting things back to whatever setting is tied to that fob.
To get it right:
Set up all your settings - seat, steering column, side mirrors, AC, radio stations
Press and release the "set" button on the door
Press the number you want (1 or 2) for about a second - it should light up
Press and release the unlock button on your keyfob - the button on the door should flash
Now repeat for driver #2.
If you unlock the car with the keyfob (rather than the button on the door handle), it will go to your settings. If you unlock with the button on the door handle and someone else drove the car last, then just press the right button on the door that corresponds to your settings. Magic.