Thank you guys so much for your replies! I hooked up some print objects at the trouble spot that Liam pointed out, and that looks like it may be at least one of my problems!
Chris: My vector size is 512, and the sample rate is 44100. I’ve not sent a thread or parallel message to poly. (Embarassingly, it slipped my mind to even try this- I kind of built this patch by getting one thing working at a time and the duplicating it… :/ )
I’ve attached the top level patch, which is just a couple of detonates that trade back and forth, but it’s very possible that I’ve sent something somewhere to the wrong inlet! (I keep reading that poly~ is one of the most difficult concepts to get your head around, so I guess this is my personal version of the struggle! ;) ) I really appreciate your help and patience! :)