So, in a way both.
When moving manually, the print head resists movement to the right much more than when moving to the left. I notice the resistance when I am about halfway across the x-axis.
When, I have a print going, or anytime the print head needs to move right, I can't tell whether it's a short or long belt issue. I am thinking it skips a tooth or something, but everything looks fine to me with the pulleys and I have tightened the belts.
This also causes the shaft to come undone in the sliding blocks which in turn causes the y-limit to not be activated since the shaft is shifted to the right. If I put the print head in the center and home it, everything is smooth. I'll see if I can get a video here.