Strange noise in front axle or in the steering column

[arturro1982]

Hello
I'm writing to you because I have got a problem with my e53 3.0d 2005. The problem is that I hear some strange noises during turning the steering wheel left or right at a small speed (10 or 15km/h) only on the holes or on the crossing railroad. When I drive fast like 30, 40 or more at straight there are no noises. I have change the left and right SWING SUPPORT. All control arms are good and I don;t know what can cause this problem. Before this my steering wheel was ok but now the second problem is that when I turn steering wheel some left or right turn on the stop I hear some "click click". I don't know is this 2 things are joint with it selfs.
A ha before this 2 problems when I drove straight and pull out my hands from the steering wheel the car was going straight and now after this problem when I have my steering wheel at center the car is going some left side.
MAybe there is something bad with my HYDRO STEERING GEAR SERVOTRONIC or there are some margin (freely)on the steering column.

thanks for any suggestion
best regards