I also have experienced a vibration when steering at low speeds. I have a 2009 A4 and when I contacted the dealer I was told that they have received a few calls about this and have now issued Technical Service Bulletin No. 2020332/2 titled "48 Servotronic steering (1N3) shudder at low speed while turning". This was originally published on March 27, 2009. The bulletin states that this is "currently under investigation" and that service departments "Do not replace any components". To this date, there is no solution to the problem.
I find the vibration to be annoying at best and the engineering team at Audi not to have a fix for this is really unnerving.
Anyone else have comments?
Thanks!