This is a 2002 Audi A4 1.8T Auto.

The shifter button is not releasing and the lock cylinder is therefore not releasing the key. I have to shake and some times hit the shifter a bit for it to release the button and then allow me take the key off the ignition.

Is this a common problem for this car? How can I fix this?

Thanks in advance.

 

I've never heard of this. I would assume the shifter would need to be replaced. You could try spraying some wd40 or contact cleaner into the button to see if that loosens it up.

 

shane, someone suggested the brake light switch. Supposly this switch controls the shifter button.

What do you think?

 

That would prevent you from shifting OUT of park and not into park. I would try, as shane stated, some wd-40 or similar.