To answer my own post; the new patch reduced audio stuttering by about 50% for me.
Pls note that in the first place, my only audio stuttering was in the really heavy scenes you get in the second half of the game. Big battles involving lots of actors, sounds, explosions, objects, etc. Like the ones in
Anticitizen One. It's one particular scene in AC1 which I use as a benchmark for stuttering. Pre-patch; stutters about 5 times throughout the battle. Post-patch; only stuttered once or twice.
I should note that last night, after the patch, I went and installed my new Audigy 2 ZS. As expected, now even those few stutters in that big battle were reduced to a very minimal level. Comparable to other games now. Very nice.
For reference, the battle I am referring to is the one which takes place right before "something" happens to Alyx. It's in an outdoor "plaza" type area in the city, Alyx is busy hacking a computer, while Combines attack from the left and right streets. You have about 2-3 resistance fighters as backup.