Z lift on extruder change (no replies)

Have a Kossel Mini with RAMPS 1.4 and Marlin; printing via Repetier host. I have successfully printed 2-color prints, but at the time the color change occurs (switch from E0 to E1) the printer Z lifts up about 5mm.

Here is the GCode at the time of the transition:

G1 X13.581 Y11.119 E12.71375
G1 X13.546 Y11.085 E12.71949
G1 F1800.000 E7.71949
G92 E0
T1
G92 E0
G1 F1800.000 E-4.00000
G92 E0
G1 X-33.273 Y5.294 F7800.000
G1 E4.00000 F1800.000
G1 X-34.953 Y4.136 E4.24239 F540.000
G1 X-35.626 Y3.807 E4.33135
G1 X-36.822 Y3.450 E4.47958
G1 X-37.373 Y3.390 E4.54540

My guess is that it's a firmware setting that's forcing the hop - it happens slicing with either Slic3r or Cura. Here's a video of the print - up to and including the lift. [1drv.ms]

Suggestions on what to check/change/etc to prevent this?

Thanks,

Dave