Just to close that thread:

The roar since ~2 years at ~70 - 80 km/h - went away when switching to sport mode.
Yesterday the TRANS FAILSAFE (first time ever)
Today after 5 kilometers - over. The X doesn't move any more.

Somehow a sad story but she will be back on the road soon.

Have a great weekend all.

Helmuth

PS: had the transmission oil changed at ~130k and 140k (km). Now I am at 155k.