Found it! After searching into the SM i found a part G001, described in the SM (page25) as a capacitor 0.1uF + resistor 120 Ohm/1Watt.
Placed it were it belongs and NO afwful noise anymore when switching off...(A Friend in Germany gave me a hint to it...:bowdown:)
Capacitor 0,1uF, typeX2 and...