I see another problem with your setup, and that is the hardware side. If you use several consumer soundcards without synchronization instead of a decent multichannel card, it might or probably will happen, that your audio will run out of sync. This means: the samples you send synchronized from the PD DSP-chain will come out of the four soundcards at different times, because each of the soundcards has a different understanding of absolute time because of slight differences in their clock chips.
i've read this in the archives. I'm not overly concerned since the sound design i've been working on has been of the ambient sound scape variety, so a little bit of drift will be fine. i am going to setup some test patches and let them run for long periods of time (eventually over a week) ... i'll keep you guys posted on how it goes.
Hmmm, i guess the problem will be that pd can't deal with the clocks running apart. I guess you will get clicks due to the fact that the 4 cards always get the signal vector at the same time.
greetings, Thomas