Rigida Grizzly CSS shudder when braking

[jimgrohn]

I got sick of replacing rims, so I decided to go the CSS path and bought a pair of Rigida Grizzly CSS.   I have put about 2000k on the rims, and everything is as expected except for a shudder from the front when braking.   I'm pretty sure the shudder is from the join in the rim.   I can see a different "shine"  on the brake surface for about 10mm either side of the join, and at slow speed I can tell the shudder is once per wheel revolution.    The shudder has been there since new.   I had hopped it would go away with a little usage, but nothing has changed.   

Anyone had this and know of the solution, or know that it will go away with more usage?

[Gog yn y De]

My RST from new had quite a step at the join on the front rim. I didn't expect it to get any better and it hasn't some +5,000km since. There's a step on the rear too but less noticeable.

I've also a pair of CSS 700C rims and there's a step on those too. Not very happy with that aspect of the finish but everything else is ok. The alternative is a non CSS rim which I don't want.

Interestingly, I've had to replace my Grizzly due to a crack appearing from one of the spoke eyelets. There are no rims available at the moment so opted for the heavier Andra 30 CSS rim - there is no step on that one.