I have set snap to grid on, grid size is set to 0.05. But all my parts moving on grid have a deviation of 0.01 in Y direction.

Moving the mousepointer always shows a deviation of 0.01 in Y direction. This you can see in the coordinat display on the lower right corner. X direction jumps in 0.05 steps as expected 4.1, 4.15, 4.2 but Y direction jumps in 0.05 steps but with wrong offset witch results in coordinates of 2.01, 2.06, 2.11

A value of 2.06 should never be possible with grid set to 0.05. In consequence all my parts are placed with an Y failure of 0.01

Changing the grid size, snap to grid on/off did not solve the problem