Remember that settings made to a Channel in one song can be carried over to the following song unless a global reset is sent to the Synth. In the case of the Ketron this can be achieved by a switching the Sound Modual off and on. Problems are created by CC11 or CC7 fading out at the end of a previous song at not reset in the next. CC64 Sustain set to 127 can create distortion in a following song. Pitchbend setting other than zero can cause later problems.

I would suggest that you include a CC121 value zero at the start of track 1 for all your songs using the Event List. This will create a soft "Reset all Controllers" each time a song is played from the start.