Some thing to consider
If you have the same mid channel on different tracks the last patch read, as the file progresses is the one that plays on all tracks sharing that channel.
At the start of play the highest number track will be the patch used, until or unless it receives another patch on the same channel.
So that seems a likely scenario . the problem is it would happen on the all GM synths.

The other time it can happen is if the receiving synth did not recognise the incoming patch or bank change sent from a channel at anytime regardless of track sent on, it normally defaults to MSB000 LSB000 Patch 0 which is piano.

Another possibility would be patch changes in the bar settings F5 in you song file.

Hope this is some help
Mike

Last edited by Mike Head; 09/23/19 12:05 PM. Reason: extra info

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