I'm just getting my first machine up and running. I used linear ball bearings on all three axis.

On my x and y axis the bearings will randomly hang up for a moment and make the motors skip some steps. There is no pattern to it. I doesn't repeat at any certain spot on the shaft.

I believe my alignment is pretty close. Do these bearings need perfection to run smoothly? Should I be looking at different bearings or are there any tricks or lubrication tips to get them running smooth?
Thanks