Flakes on Siraya tech blu part - peopoly phenom noir

Hi all,

I print with Siraya Tech Blu on Peopoly Phenom Noir. Often my products have ‘flakes’ on them, which decreases surface quality. An example is seen in the attachment! These parts were printed using the Peopoly Moai heater, which keeps the temperature between 27 and 35 degrees C. Does anyone know how I can improve my surface quality?