Hi there,
I had my tranny rebuilt and the above described annoyance shifted down from 50km/h to 40km/h and reduced in quantities and strength,as well as the famous rear end Bang,some times it's downshifting that I can feel it did,but I got only one Bang in 3 month now.It happens only when Throttle Position is sending 0.5amps to the ECU,everything above that doesn't provoke it at all.
The tranny's module was re flashed and a part of the valve body was replaced along some solenoids.
From my own experience if you are about to get your tranny rebuilt,or do it yourself,like some people here or get it done by the dealership.
That shuddering never happens in S mode,so it should be some kind of software/hardware glitch,imo.
Also my tranny is loud between shifting at sub operative temps.
Almost forgot to write,it seems to act worse if my battery is weak.