I just bought a new Lulzbot Taz Pro which has dual extrusion. The second extruder will not move when it is about to print so it is extruding filament in above the print bed.
When the print switches from the first extruder to the second extruder it does not move down, so when it begins to print the filament just dangles from the extruder and ends up clumping together and not sticking to the bed.
I've tried manually adjusting the heights of the extruders up and down but the second extruder will not move. I am not sure if this is a defect with the machine or if the was something i did wrong during the set up.