@proclaim, this only happens with the Slic3r engine. When a print starts, after the calibration the temperature remains at 170C. Flux tries to extrude at 170C, without waiting for the temperature to reach the set level.
I have printed with both slicer options, under windows 10, I do not have this issue. I have not tried with my Mac as of yet, hopefully tonight.
I forgot to mention, I am on Mac os 10.11.6.