From what I've seen in the forums, this appears to be an ongoing issue. However, in my situation the target was working fine up until a few versions ago where it suddenly became super jittery.
We're using a Cylindrical target that has a rating of 2, but that's due to the nature of the target.
As an image target, it has a rating of 5 stars.
The target is going on one half of a large column at a tradeshow, so size isn't an issue.
Does anyone have any tips on how to reduce the jitters, or maybe know why it's moving all of a sudden?