Well Jim, if everything else fails, you might want to try changing the SYS(3) call, that might give you duplicate results, with SYS(2015), which ensures no duplicates. I am not sure if it helps, but I do not think it will hurt :)
"The five senses obstruct or deform the apprehension of reality."
Jorge L. Borges?
"Premature optimization is the root of all evil in programming."
Donald Knuth, repeating C. A. R. Hoare
"To die for a religion is easier than to live it absolutely"
Jorge L. Borges