Bubbling Layers

I am currently using a ORD-MH3000 and repetier host. I have tried printing a human head using PET+ filament at a 0.1mm layer height. When it was finished I noticed a difference in perimeter for several layers where it is slightly indented and has a bubbled texture. I also get a similar problem printing in ABS at this resolution. Has anybody else encountered a similar problem?

Full Head

Close-Up


Any help is appreciated.