This thread contains reports of different things happening with different MIDI and FC controllers connected, so it seems unlikely that there is a common problem here. Of course it is possible that there's an unusual bug in play, but if so, we haven't experienced or reproduced it.
I think it's unlikely that an FC switch could cause "preset scrolling" or jumping randomly to different presets (500->30), since neither of these things is normally possible on the FC. I suppose it is possible that a PRESET +1 switch could be triggering repeatedly, but no one has said whether or not they are using such a switch, and a problem like this might not limit itself to one function. In other words, if you changed the layout, you'd perhaps see that same switch misfiring and doing other things like changing scenes, toggling an effect on and off, etc.
As for 3rd party MIDI controllers doing strange things, I can't be of much help there, except to share that I see two scenarios in support cases. One is that the controller is sending bad data, and the other is that good data is being corrupted in transit (cable, interference, etc.)
The last thing I'll mention, and this is very rare, is that a stuck front panel NAV button can cause presets to "scroll." To remedy this, you can usually just gently work the buttons. Turn the unit off, press and release the buttons several times, then press, gently push, and move your finger in a circle, before releasing.
