Seems to me to be a design or manufacturing quality issue. The spacer must be the right length so that there is no lateral stress on the inner race of the brake side but also not slop around loose when the axle is tightened. I would try and run a vernier thru the hub and measure the outer race seat to seat distance and make sure the spacer is the same length. If the spacer is longer as per your findings either the spacer needs to be shortened or there needs to be a thin washer type landing created the thickness of the difference to keep the bearing on the sprocket side from being pressed in to far. Looks like the manufacturer of the hubs is having 2 issues: 1. Not changing his tool tip as often as needed so as the tool wears the diameter of the bearing bores gets smaller during CNC milling process. 2. Spacers are not made to the correct length or the hub milling depth specification is off. Woody should be able to determine if it is better to shorten the shaft or add the thin washer. He will ened to check how the sprocket cush assembly and bearings and spacers will fit when the change is made. Looks like a very valid analysis to me BlueBull2007. Thanks for sharing with the forum.