I think Audi beefed up the synchros on late 2000's/early 2001's and newer S4's so the 1-2 shift happens with a bit of a snag.

I've driven early 2000's and they do a 1-2 shift smoother without any tricks.

On my 2001, I get good results by simply not completely lifting off when doing the 1-2 shift. Note that I'm not powershifting at all... clutch still goes in as usual except I don't completely lift off throttle. I usually get smoother and faster 1-2 shifts that way.

Give that a try.

larryV
01S4 + mods