It's kind of hard to tell are those waves in the layers?

To me it looks a little bit like corner ringing look at this tuning site I found it goes over it pretty well
http://www.makerbot.com/sailfish/tuning

If I am off base I also use this site for other issues http://support.3dverkstan.se/article...shooting-guide

Let me know if it looks like it is what you are seeing or if none of those fix the issue