Multiplot charts don't work on the PDA module, but multiplot XY graphs should work (at least they have for me). I have noticed a problem when trying to use events on controls of different types or representations. Is all your data identical in format? Try building a simple application with a multiplot XY graph with demo data and see if it works on your PDA. If it does, see if you can find the difference in data between the two apps. I understand that you ran this with a different graph for each input, so you've determined that the problem comes from the multiplot graph, right?
If I remember correctly, a multiplot graph can only display 8 plots. Are you trying to display more?
If all of this didn't help, you should post your code (At least the most simplified version that still has the error).
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