A4 2.5 tdi CVT problem

Have a customers Audi A4 2.5 tdi CVT giving trouble as follows:

1) when car is running to operating temperature the temperature dial suddenly drops downwards
2) the traction control light comes on
3) shudder comes into car (CVT gearbox problem??)
4) after the above happens if coming to a standstill in car its as if the brakes are stuck on.

We are aware of the problems with the CVT box but this seams just a little different.No faults showing up and the indicator on the dash for which gear you are in is acting normally.

Please can anyone shed a little light on this matter
:confused::confused:

Did you get anywhere with this issue? My car has similar symptoms and looks like the throttle valve actuator, was wondering if you concluded the same?