This bug is best demonstrated using video:
https://youtu.be/HT4vKGCBS2gRegularly but so far not predictably, the KSP will stop progressing the transport when step record is engaged. Once this occurs it is persistent on the track until either the unit is turned off or a different project is chosen. You can clear the pattern but this does not restore the ability to step record.
This seems to always occur if "sticky notes" have also occurred. This is present with the latest firmware 1.3.1 after a hardware reset was done and no old projects imported.