Print stuttering/pausing

[earache]

I'm having trouble with a print and was wondering if anyone had any ideas on how to fix it.

This particular print has pretty simple geometry, essentially a box with rounded corners. It starts printing fine but after about 40 layers it starts pausing at a specific points on the outer perimeter, https://youtu.be/cNskWD8vFjI Once this starts happening it seems to remain consistent on subsequent layers, pausing in the same places. Unfortunately this pausing eventually ruins the print because the printer stops extruding consistently directly after the pauses.

I've seen this occur on some other prints, typically along rounded corners and it can usually be resolved by refining the STL model, but not in this case. I ran the model through netfabb, sliced in Cura and printed on Repetier. Printer is an Airwolf 3d HD2X. gcode attached.

Any ideas? Thanks.

Eric