freezes for 3-5seconds mbp10,1 13" retina

Hi All,

Ubuntu works pretty well on my MBP 10,1. It is a 13" (so intel 4000) and a i5 with 8gb.

Its starting to get seriously annoying. I am forever hitting these random 3-5 second freezes when doing stuff. I will be scrolling down a page or typing, pc will freeze for a few seconds then catch up.

Any got any suggestions what I can do?

I boot into ubuntu using Refind...