Topic: Totalmix-Routing: Ableton->Waves Multirack

Hello there  :-)

I got a problem here; Help would be much aprecciated.
I would like to fire up an audiotrack from ableton live and get its audio in a waves-multirack-slot in order to (auto-)process it there (ducking etc.) in conjunction with an incoming livemikrophone-mix.
Done so far: I can manage to grab the signal from ableton in multirack (via activating the »loopback«-function in Totalmix), but ableton still plays the audio as well so I got it twice.
Question: How is it possible to play the Audio from Ableton and get it to listen ONLY from the target app (->Waves Multirack)? Anyone a hint?

Thanks in Advance  :-)
k.