Ive found the solution! For the Audix 4506 DVD player that is.
Here is how to make it Region Free:

1) Open the DVD Hatch, with no CD in it.
2) Then you can put in the code "2812"
3) Then you will get a menu, choose your region here.

You can choose 1 among theese:
Region 1
Region 2
Region 3
Region 4
Region 5
Region 9

Region 9 is the region free setting.

I hope this helps, it worked for me.