had the same with the shimano stuff, now changed the whole setup to SRAM X9, with the 1:1 technology.
Perfectly direct and smooth shifting. No noice at all.
With the 1:1 technology there is more cable movement between each gear.
We have the nice carbon levered 6703 Ultegra 10spd brifters which work perfectly and do not require extraneous trimming. We do use a XTR 9spd rear derailleur that has the same throw ratio as the official 10spd ones, so no problem there.
Curious how you are using Dura Ace brifters as part of a 10spd / triple setup, since there are no DA designed for that config? Are you using 9spd DA triple brifters or DA brifters for a 10spd double ring setup? Plus what other components are you using that are not officially for 10spd?
My 9 sp Ultegra brifter and FD shifts 10 speed rings perfectly. It's fussy, but I can adjust it so it doesn't need a trim with any ring/cog combination that I use. I don't use the smallest cog with the middle ring, the largest two cogs with the big ring, nor the smallest 4 cogs with the inner ring. I notice that when my middle ring gets worn, shifting suffers and the adjustment gets trickier. New ring fixes that.