2011 s 550 tachometer moves when press bottons
 

High i just bought a 2011 s 550 with 60000 miles car was one onwer bought an maintained at same dealer it is imaculate they wanted $ 6800 for a warranty
and based on the history and car being so clean i did not buy one.

I noticed when: no key in door open that if i press certain button in center dash or on center console the tach will move down slightly and u have to wait about a minute to repeat it. Now it shows no signs of any thing being wrong anywhere.

I ask MB to explain it an they say they never seen it before and reran diagnostics n nothing came up!

So was wondering if any one has ever seen this