[Bug?] Wierd behavior with jitter stopping output

Hello board,

I've been trying to build some effects for models in Jitter before (thread: https://cycling74.com/forums/index.php?t=msg&th=32513&start=0&rid=5118&S=2acef99bdc4239316a3a47066c54051f) but with limited success. This example features an apple with noise instead of z-coordinates. So far, I found a total of 4 ways to turn off my output when it shouldn't, to my knowledge.

The following movie illustrates this:
http://smadsteck.nl/Matrixmodel.mov

- Attaching the jit.unpack to a jit.pwindow (did not always occur)
- Moving another object connected to jit.unpack to the left of the bang object
- Selecting a certain jit.pwindow
- Sending an extra bang to the jit.noise object (even when disconnecting the original connection, it doesn't work)

Does anyone have any idea what the logic behind this is? And can anyone reproduce this behavior? When checking on the matrix ids being passed around, all of them are different, so one shouldn't influence another. This makes it pretty impossible to create any kind of effect for me...

And of course, here's the patch: