No, it's just a matter of settings when generating the gcode. That doesn't appear to be a mechanical error, and it's not a software bug,
Simply just not enough plastic being put down on each layer and since it's a circle, the layer pulls in from shrinkage. (As Yanisin described in his post) I imagine that part is pretty weak from the poor bonds between layers.
Quick fix is that when generating gcode using print-o-matic settings, go to the last tab of print o matic and change the diameter from 9.98 to something smaller like 8.98 or 7.98. Recently, in order to fix some similiar issues, I went as low as 6.6 diameter with no issues. This makes the software think it needs to turn the extruder motor more to get enough filament so it actually pushes more filament with a smaller number.
Tip of the day is that while using less plastic makes the part finish look better (like surface fill) it also makes very weak bonds between vertical layers and cause a whole host of other issues such as wierd problem like this. More palstic is better.
Also, reducing infill to 10% or less is advisable and helps limit heat retention, thus less warping a cracking of parts.