I put a trace(this) on an MC.

Output:

_level0.nbMC.mgMC.B2MC
_level0.nbMC.B2MC
_level0.nbMC.B2MC
(etc)

First time it appears correctly. B2MC is indeed in mgMC.

Every time subsequently it is called, it is reporting itself as being one object higher up.

What would cause it to "jump" a level??

And I put in a test button on the top level to advance B2MC to the nextFrame, just to see if I can control it/address it, and neither path seems to work.