Minor detail that is upsetting me

Hi everyone
I've been improving my printings but have some final issue that's bothering me and I am not able to figure out what's going on.

This print (image attached) was printed using 0.1mm layer height and 100% infill.

I am using Repetier host with Cura Slicing...
Used 1.2 Shell thickness
1.2 top/bottom thickness
40% infill overlay

As you see in the pictures there are fails near the holes and more far from a hole. The top of the print (that highest part) however came flawlessly...so I discard top layer thickness right ?
Any sugestions / help would be very much appreciated

kind regards

Part of the problem is under extrusion (based on the gaps in the top solid fill), and the gaps around part of the circle suggest a degree of back-lash. The holes you arrowed in 20160323_013237.jpg are a bit of a mystery. In one case it looks like the entire line gradually petered out before the hole happened - maybe a slipping extruder gear?

Solved most of the gaps by increasing extruder multiplier but cant fix the gaps between holes and infill
Extruder gear doesnt seem to be slipping

I have similar defects at times, sometimes when the filament pops, I'm assuming because of moisture in the filament it will leave these gaps. Also, I notice that if at the times the filament has to yank on the spool to get filament extruded, that it leaves less filament at that spot. I also of a bowden tube that has way more friction than I'd like and it gets worse if there is a lot of retraction, this makes it harder for the extruder to extrude, but that would show a little more continuous problem of gaps and such, so I'd suspect something minor restricting extrusion.