I had same awful noise in same situation (out of saddle with bike moving side to side) with alloy steerer forks on my Specialized Allez Elite and after changing everything around the only thing that shut it up was swapping out the forks completely.
@dubtap started
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I had same awful noise in same situation (out of saddle with bike moving side to side) with alloy steerer forks on my Specialized Allez Elite and after changing everything around the only thing that shut it up was swapping out the forks completely.