I was not careful enough to check the gcode before I started printing. The result was the white frames (both the outer and around the warning) is not really joined as expected.
Also, when I changed to the red filament I had not primed the nozzles sufficiently, resulting the a bad first layer with the red, and as a result of that, a bad second layer.
0-1.2 mm: Black
1.4- mm: Red