A90: electrical noise and weird downshift

[Gregory Deschodt <GDeschodt@synon.com>]

Morning folks, 

A couple of newbie questions about my wife's car... it's a 91 A90
automatic.

- When cold, the engine has a "tac-tac-tac-tac-tac" sound (valves ?
lifters?) ... 
   any idea what I can do about this? 
- There is a permanent electric "whine" of some kind that you can hear
from inside the car. 
  I've tracked the noise to the rear passenger side, behind the wheel.
There seems to be some
  electrical device there but I have no idea what it is (I have no
manual or anything).. Any clue ?
  Remedy ? 
- Most bizarre: when the car slows down, it automatically downshifts
into a lower gear,
  as it should, but in the process you can hear a quick "noise" like the
tires are spinning or
  are locked for 1/2 a second or something... ??

Many thanks in advance for all tips !  

Greg. Wife's 91 A90
911 SC , 65 Karmann ghia cabrio