TL-3d pro dual extrusion shifting

Hello everybody.
A new problem arise on my TL-3d pro during dual extrusion on model. I used the left extruder for support and right extruder for final printing material.
My problem is that right extruder shifts on y-axis after the first change of extruder.
Before support needed, no problem. At first layer support, when switching another time to right extruder, a shift occurs and only this time.
A put a photo which illustrates the problem.
Have any ideas ?

Thank you for helps.
Seb.