Dual Extrusion issues with Creator Pro

[kevbo]

Hey everyoneMy Creator Pro (2019) struggles with the dual extrusion, since the upgrade to the all metal hotend for both extruders. The problem is as follows:First layer works fine, starting with the right extruder followed by the left one. But then when the second layer starts and changes back to right extruder the filament does not extrude anymore and you hear a rattle from the stepper motor. It seems that the filament can not be pushed down (even pushing down by hand doesn't work). Does somebody have the same problems?I tried already different filaments and slicer-programs but the issue remains. After cancel the print, I use the "load filament" function and it extrudes fine again. Single extrusion works completely fine as well.