Thanks Sam for your comments, and I may have noticed something similar with the strings. I did this mix very fast and so am going to check it out.
I guess I should mention this piece was based on a band piece I wrote in 1978 (dating myself I know) that was "Symphony for Band" and this was the last movement. It was expanded a lot from the band version and I turned it into a tone poem in 1994. That was yet another version with a much larger orchestration, and was played in rehearsal at the University of Nevada Reno and sounded pretty bad. I still have that score though - it was somewhat inspired by my reading "Grettir the Strong" a Norse saga, about a violent outlaw who goes back and forth between Norway and Iceland getting in fights then finally gets killed by a mob of angry villagers. He can ony be killed by a large number of heavily armed opponents. In the previous version it ended as loudly as I could write, with FFFs for massed brass and percussion, but in this later version it ends softly, lamenting his death (though all the people related to those he killed were probably glad).