Hi RC,
probably you have accidentally saved so called "Keyboards Voice Meta Events" into your MIDI file.
First please check the settings in "Song Creator > Setup tab": If there is ticked the item "Keyboard Voice", REMOVE this checkmark.
If "Keyboard Voice" is
ticked there, then whenever you press SAVE in the Song Creator,
your current Keyboard Voice settings are saved into the MIDI file,
at the current song position (e.g. at measure 4).
As you know, you can only save the Voice settings made for the MIDI file channels (in the Mixing Console) at the BEGINNING of the file (by first pressing the Song
Stop button, then pressing "Execute" in the Song Creator (Setup tab), and finally on SAVE). The keyboard voice settings can, as I said, be saved in the file at any position in the song.
The easiest way to remove unwanted Keyboard Voice Events from MIDI files is with the PC program "PSRUTI":
>>>
https://heikoplate.de/psruti.html- Load the file into PSRUTi.
- Click Extras > Delete Keyboard Events.
- Leave at least the upper item checked ("Delete Meta Events Keyboard Voice").
- Click Ok > Ok > Exit.
- Click "Save" (this will overwrite your source file!) or "Save as" (to save a
new file).
- Exit PSRUTI.
- Finished!

You can also delete these Keyboard Voice Events in the
Song Creator on the keyboard, but it's not that easy. If you want to do this, please come back here!
Best regards,
Chris