ICBF problem?

So I have these two cuelists.

one contains, amongst other things, an intensity effect and position effect for some lights. the other is an IPCB fader with just intensity information for the same lights.

I push the IPCB fader up and it over-rides the intensity effect on the other master correctly. I pull it down and go to the next cue in the other list and that fades correctly. If I leave the IPCB fader up and go to the next cue, all the lights that are supposed to be doing a beautiful position effect snap to the base position of the effect for a second or so, then snap back to the effect.

this looks a bit pants.

anybody?
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