Answering my own post

I may have found the answer to what I was seeing.

I was working with another purchased MIDI file that I hadn't revisited in quite some time. After working with it I remembered why I had shelved it.

After that MIDI played once all the tracks were silent when playing it again!

If I changed the Channel on one of the tracks that was now silent I had sound again, which is similar to what I was seeing with the MIDI that prompted this thread.

I did some exploration and the new MIDI I was working with sets the expression controller on all of the instrument tracks, and the last thing it did with the expression was set it to 0!

Then in each track as the last thing sent they did a reset all controllers.

But it appears that Ketron does NOT reset the expression controller on a reset all controllers. At least it does not reset it to max.

I tested this theory by adding a CC event at the start of each instrument track to set expression to 127 (max).

This worked reliably, so probably I have another MIDI file that is setting expression to 0 on channel 1.

Burt