Sorry, I missed that your are saying your headset is loose, not tight.
If you have a set of calipers, measure the cup versus the bearing. I found my to be a little loose on my IP-036 but when I looked up the spec, I found that both were just barley in spec, however, my cup was on the large side and my bearing was on the small side. However, I don't think the difference was nearly as much as yours. It's possible you have the wrong size top headset bearing.