Reordering certain plugins causes others to lose/corrupt state

1. Summary/Title
Reordering certain plugins causes others to lose/corrupt state.

2. Description

  1. Start a new project
  2. Add one of the following plugins (part of the MIDI Tools suite of plugins from the app store): MIDI Clone & Filter, MIDI Route, MIDI Key Zone or MIDI Bus to track 1.
  3. Add a Mozaic script with some random data added to the code window
  4. Do the same as (2/3) but on a second track, adding different data to the Mozaic window
  5. Drag the MIDI Bus plugin to the bottom of the chain in the first track.
  6. The Mozaic in track 1 now has the state of the one in the second track. It doesn’t always work like this first time but if you then move MIDI Bus back to slot 1 in the chain then you should see that Mozaic has either taken on the state of the other instance or has reset its state. Try dragging the plugins around in both tracks to see random state corruption.

I did quite an extensive test of other plugins but the issue was seen only when reordering the ones mentioned from the MIDI Tools suite. Note that the problem does not strictly affect Mozaic, I have also (for example) seen Atom lose or swap its state when one of the MIDI Tools plugins is moved around with them in the chain.

There may be a bug in the affected plugins which is causing this, but this should not be able to corrupt the state of other unrelated MIDI plugins. The same behaviour is not seen when reordering the same plugins in NanoStudio 2, for example.

3. Expected Results
Reordering plugins should not affect the state of others in the chain.

4. Actual Results
Other plugins lose state or take on the state of plugins from other tracks.

5. Environment
Air 4, latest CB 3.3, iOS 14.4.2

I have tested and this is resolved in 3.3.1. Thanks @LSlowak and team!

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